diff --git a/dom/base/FormData.cpp b/dom/base/FormData.cpp
index c113d1243621..a74a262c35e8 100644
--- a/dom/base/FormData.cpp
+++ b/dom/base/FormData.cpp
@@ -16,7 +16,7 @@ using namespace mozilla;
 using namespace mozilla::dom;
 
 FormData::FormData(nsISupports* aOwner)
-  : nsFormSubmission(NS_LITERAL_CSTRING("UTF-8"), nullptr)
+  : HTMLFormSubmission(NS_LITERAL_CSTRING("UTF-8"), nullptr)
   , mOwner(aOwner)
 {
 }
@@ -99,7 +99,7 @@ NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(FormData)
 NS_INTERFACE_MAP_END
 
 // -------------------------------------------------------------------------
-// nsFormSubmission
+// HTMLFormSubmission
 nsresult
 FormData::GetEncodedSubmission(nsIURI* aURI,
                                nsIInputStream** aPostDataStream)
diff --git a/dom/base/FormData.h b/dom/base/FormData.h
index 00652e8411ce..a7ab3b9b3d9a 100644
--- a/dom/base/FormData.h
+++ b/dom/base/FormData.h
@@ -10,11 +10,11 @@
 #include "mozilla/Attributes.h"
 #include "mozilla/ErrorResult.h"
 #include "mozilla/dom/BindingDeclarations.h"
+#include "mozilla/dom/HTMLFormSubmission.h"
 #include "mozilla/dom/File.h"
 #include "mozilla/dom/FormDataBinding.h"
 #include "nsIDOMFormData.h"
 #include "nsIXMLHttpRequest.h"
-#include "nsFormSubmission.h"
 #include "nsTArray.h"
 #include "nsWrapperCache.h"
 
@@ -26,7 +26,7 @@ class GlobalObject;
 
 class FormData final : public nsIDOMFormData,
                        public nsIXHRSendable,
-                       public nsFormSubmission,
+                       public HTMLFormSubmission,
                        public nsWrapperCache
 {
 private:
@@ -104,7 +104,7 @@ public:
 
   const OwningBlobOrUSVString& GetValueAtIndex(uint32_t aIndex) const;
 
-  // nsFormSubmission
+  // HTMLFormSubmission
   virtual nsresult
   GetEncodedSubmission(nsIURI* aURI, nsIInputStream** aPostDataStream) override;
 
diff --git a/dom/html/HTMLButtonElement.cpp b/dom/html/HTMLButtonElement.cpp
index 9c80efae67c9..874383fb925b 100644
--- a/dom/html/HTMLButtonElement.cpp
+++ b/dom/html/HTMLButtonElement.cpp
@@ -6,7 +6,9 @@
 
 #include "mozilla/dom/HTMLButtonElement.h"
 
+#include "HTMLFormSubmissionConstants.h"
 #include "mozilla/dom/HTMLButtonElementBinding.h"
+#include "mozilla/dom/HTMLFormSubmission.h"
 #include "nsIDOMHTMLFormElement.h"
 #include "nsAttrValueInlines.h"
 #include "nsGkAtoms.h"
@@ -14,9 +16,6 @@
 #include "nsStyleConsts.h"
 #include "nsPresContext.h"
 #include "nsIFormControl.h"
-#include "nsIForm.h"
-#include "nsFormSubmission.h"
-#include "nsFormSubmissionConstants.h"
 #include "nsIURL.h"
 #include "nsIFrame.h"
 #include "nsIFormControlFrame.h"
@@ -440,7 +439,7 @@ HTMLButtonElement::Reset()
 }
 
 NS_IMETHODIMP
-HTMLButtonElement::SubmitNamesValues(nsFormSubmission* aFormSubmission)
+HTMLButtonElement::SubmitNamesValues(HTMLFormSubmission* aFormSubmission)
 {
   //
   // We only submit if we were the button pressed
diff --git a/dom/html/HTMLButtonElement.h b/dom/html/HTMLButtonElement.h
index 2151fe09f394..ecd9e03d7388 100644
--- a/dom/html/HTMLButtonElement.h
+++ b/dom/html/HTMLButtonElement.h
@@ -49,7 +49,7 @@ public:
   // overriden nsIFormControl methods
   NS_IMETHOD_(uint32_t) GetType() const override { return mType; }
   NS_IMETHOD Reset() override;
-  NS_IMETHOD SubmitNamesValues(nsFormSubmission* aFormSubmission) override;
+  NS_IMETHOD SubmitNamesValues(HTMLFormSubmission* aFormSubmission) override;
   NS_IMETHOD SaveState() override;
   bool RestoreState(nsPresState* aState) override;
   virtual bool IsDisabledForEvents(EventMessage aMessage) override;
diff --git a/dom/html/HTMLFieldSetElement.cpp b/dom/html/HTMLFieldSetElement.cpp
index 46c825138e88..30728f128d1b 100644
--- a/dom/html/HTMLFieldSetElement.cpp
+++ b/dom/html/HTMLFieldSetElement.cpp
@@ -154,7 +154,7 @@ HTMLFieldSetElement::Reset()
 }
 
 NS_IMETHODIMP
-HTMLFieldSetElement::SubmitNamesValues(nsFormSubmission* aFormSubmission)
+HTMLFieldSetElement::SubmitNamesValues(HTMLFormSubmission* aFormSubmission)
 {
   return NS_OK;
 }
diff --git a/dom/html/HTMLFieldSetElement.h b/dom/html/HTMLFieldSetElement.h
index a84f452f0a77..d169434ae84c 100644
--- a/dom/html/HTMLFieldSetElement.h
+++ b/dom/html/HTMLFieldSetElement.h
@@ -51,7 +51,7 @@ public:
   // nsIFormControl
   NS_IMETHOD_(uint32_t) GetType() const override { return NS_FORM_FIELDSET; }
   NS_IMETHOD Reset() override;
-  NS_IMETHOD SubmitNamesValues(nsFormSubmission* aFormSubmission) override;
+  NS_IMETHOD SubmitNamesValues(HTMLFormSubmission* aFormSubmission) override;
   virtual bool IsDisabledForEvents(EventMessage aMessage) override;
   virtual nsresult Clone(mozilla::dom::NodeInfo *aNodeInfo, nsINode **aResult) const override;
 
diff --git a/dom/html/HTMLFormElement.cpp b/dom/html/HTMLFormElement.cpp
index 820c89724b41..9b30636a29d1 100644
--- a/dom/html/HTMLFormElement.cpp
+++ b/dom/html/HTMLFormElement.cpp
@@ -36,6 +36,7 @@
 #include "nsQueryObject.h"
 
 // form submission
+#include "HTMLFormSubmissionConstants.h"
 #include "mozilla/dom/FormData.h"
 #include "mozilla/Telemetry.h"
 #include "nsIFormSubmitObserver.h"
@@ -50,7 +51,6 @@
 #include "nsIInterfaceRequestorUtils.h"
 #include "nsIWebProgress.h"
 #include "nsIDocShell.h"
-#include "nsFormSubmissionConstants.h"
 #include "nsIPrompt.h"
 #include "nsISecurityUITelemetry.h"
 #include "nsIStringBundle.h"
@@ -644,7 +644,7 @@ HTMLFormElement::DoSubmit(WidgetEvent* aEvent)
   mIsSubmitting = true;
   NS_ASSERTION(!mWebProgress && !mSubmittingRequest, "Web progress / submitting request should not exist here!");
 
-  nsAutoPtr<nsFormSubmission> submission;
+  nsAutoPtr<HTMLFormSubmission> submission;
 
   //
   // prepare the submission object
@@ -684,7 +684,7 @@ HTMLFormElement::DoSubmit(WidgetEvent* aEvent)
 }
 
 nsresult
-HTMLFormElement::BuildSubmission(nsFormSubmission** aFormSubmission,
+HTMLFormElement::BuildSubmission(HTMLFormSubmission** aFormSubmission,
                                  WidgetEvent* aEvent)
 {
   NS_ASSERTION(!mPendingSubmission, "tried to build two submissions!");
@@ -722,7 +722,7 @@ HTMLFormElement::BuildSubmission(nsFormSubmission** aFormSubmission,
 }
 
 nsresult
-HTMLFormElement::SubmitSubmission(nsFormSubmission* aFormSubmission)
+HTMLFormElement::SubmitSubmission(HTMLFormSubmission* aFormSubmission)
 {
   nsresult rv;
   nsIContent* originatingElement = aFormSubmission->GetOriginatingElement();
@@ -1033,7 +1033,7 @@ HTMLFormElement::NotifySubmitObservers(nsIURI* aActionURL,
 
 
 nsresult
-HTMLFormElement::WalkFormElements(nsFormSubmission* aFormSubmission)
+HTMLFormElement::WalkFormElements(HTMLFormSubmission* aFormSubmission)
 {
   nsTArray<nsGenericHTMLFormElement*> sortedControls;
   nsresult rv = mControls->GetSortedControls(sortedControls);
@@ -1609,7 +1609,7 @@ HTMLFormElement::FlushPendingSubmission()
   if (mPendingSubmission) {
     // Transfer owning reference so that the submissioin doesn't get deleted
     // if we reenter
-    nsAutoPtr<nsFormSubmission> submission = Move(mPendingSubmission);
+    nsAutoPtr<HTMLFormSubmission> submission = Move(mPendingSubmission);
 
     SubmitSubmission(submission);
   }
diff --git a/dom/html/HTMLFormElement.h b/dom/html/HTMLFormElement.h
index 6c6792297fea..11f2d6265a51 100644
--- a/dom/html/HTMLFormElement.h
+++ b/dom/html/HTMLFormElement.h
@@ -9,11 +9,11 @@
 
 #include "mozilla/AsyncEventDispatcher.h"
 #include "mozilla/Attributes.h"
+#include "mozilla/dom/HTMLFormSubmission.h"
 #include "nsAutoPtr.h"
 #include "nsCOMPtr.h"
 #include "nsIForm.h"
 #include "nsIFormControl.h"
-#include "nsFormSubmission.h"
 #include "nsGenericHTMLElement.h"
 #include "nsIDOMHTMLFormElement.h"
 #include "nsIWebProgressListener.h"
@@ -283,7 +283,7 @@ public:
    *
    * @param aFormSubmission the form submission object
    */
-  nsresult WalkFormElements(nsFormSubmission* aFormSubmission);
+  nsresult WalkFormElements(HTMLFormSubmission* aFormSubmission);
 
   /**
    * Whether the submission of this form has been ever prevented because of
@@ -481,14 +481,14 @@ protected:
    * @param aFormSubmission the submission object
    * @param aEvent the DOM event that was passed to us for the submit
    */
-  nsresult BuildSubmission(nsFormSubmission** aFormSubmission,
+  nsresult BuildSubmission(HTMLFormSubmission** aFormSubmission,
                            WidgetEvent* aEvent);
   /**
    * Perform the submission (called by DoSubmit and FlushPendingSubmission)
    *
    * @param aFormSubmission the submission object
    */
-  nsresult SubmitSubmission(nsFormSubmission* aFormSubmission);
+  nsresult SubmitSubmission(HTMLFormSubmission* aFormSubmission);
 
   /**
    * Notify any submit observers of the submit.
@@ -590,7 +590,7 @@ protected:
   bool mSubmitInitiatedFromUserInput;
 
   /** The pending submission object */
-  nsAutoPtr<nsFormSubmission> mPendingSubmission;
+  nsAutoPtr<HTMLFormSubmission> mPendingSubmission;
   /** The request currently being submitted */
   nsCOMPtr<nsIRequest> mSubmittingRequest;
   /** The web progress object we are currently listening to */
diff --git a/dom/html/nsFormSubmission.cpp b/dom/html/HTMLFormSubmission.cpp
similarity index 98%
rename from dom/html/nsFormSubmission.cpp
rename to dom/html/HTMLFormSubmission.cpp
index 2acb50d85b20..786384eeb40c 100644
--- a/dom/html/nsFormSubmission.cpp
+++ b/dom/html/HTMLFormSubmission.cpp
@@ -4,7 +4,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#include "nsFormSubmission.h"
+#include "HTMLFormSubmission.h"
 
 #include "nsCOMPtr.h"
 #include "nsIForm.h"
@@ -40,11 +40,8 @@
 #include "mozilla/dom/EncodingUtils.h"
 #include "mozilla/dom/File.h"
 
-using namespace mozilla;
-using mozilla::dom::Blob;
-using mozilla::dom::Directory;
-using mozilla::dom::EncodingUtils;
-using mozilla::dom::File;
+namespace mozilla {
+namespace dom {
 
 static void
 SendJSWarning(nsIDocument* aDocument,
@@ -715,7 +712,7 @@ nsFSTextPlain::GetEncodedSubmission(nsIURI* aURI,
 
 nsEncodingFormSubmission::nsEncodingFormSubmission(const nsACString& aCharset,
                                                    nsIContent* aOriginatingElement)
-  : nsFormSubmission(aCharset, aOriginatingElement)
+  : HTMLFormSubmission(aCharset, aOriginatingElement)
   , mEncoder(aCharset)
 {
   if (!(aCharset.EqualsLiteral("UTF-8") || aCharset.EqualsLiteral("gb18030"))) {
@@ -806,7 +803,7 @@ GetEnumAttr(nsGenericHTMLElement* aContent,
 nsresult
 GetSubmissionFromForm(nsGenericHTMLElement* aForm,
                       nsGenericHTMLElement* aOriginatingElement,
-                      nsFormSubmission** aFormSubmission)
+                      HTMLFormSubmission** aFormSubmission)
 {
   // Get all the information necessary to encode the form data
   NS_ASSERTION(aForm->GetComposedDoc(),
@@ -873,3 +870,6 @@ GetSubmissionFromForm(nsGenericHTMLElement* aForm,
 
   return NS_OK;
 }
+
+} // dom namespace
+} // mozilla namespace
diff --git a/dom/html/nsFormSubmission.h b/dom/html/HTMLFormSubmission.h
similarity index 90%
rename from dom/html/nsFormSubmission.h
rename to dom/html/HTMLFormSubmission.h
index 98e38842dbde..3a66b2a726f4 100644
--- a/dom/html/nsFormSubmission.h
+++ b/dom/html/HTMLFormSubmission.h
@@ -3,14 +3,15 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-#ifndef nsIFormSubmission_h___
-#define nsIFormSubmission_h___
+
+#ifndef mozilla_dom_HTMLFormSubmission_h
+#define mozilla_dom_HTMLFormSubmission_h
 
 #include "mozilla/Attributes.h"
-#include "nsString.h"
 #include "nsCOMPtr.h"
 #include "nsIContent.h"
 #include "nsNCRFallbackEncoderWrapper.h"
+#include "nsString.h"
 
 class nsIURI;
 class nsIInputStream;
@@ -19,20 +20,19 @@ class nsIMultiplexInputStream;
 
 namespace mozilla {
 namespace dom {
+
 class Blob;
-} // namespace dom
-} // namespace mozilla
 
 /**
  * Class for form submissions; encompasses the function to call to submit as
  * well as the form submission name/value pairs
  */
-class nsFormSubmission
+class HTMLFormSubmission
 {
 public:
-  virtual ~nsFormSubmission()
+  virtual ~HTMLFormSubmission()
   {
-    MOZ_COUNT_DTOR(nsFormSubmission);
+    MOZ_COUNT_DTOR(HTMLFormSubmission);
   }
 
   /**
@@ -53,7 +53,7 @@ public:
    * not null.
    */
   virtual nsresult AddNameBlobOrNullPair(const nsAString& aName,
-                                         mozilla::dom::Blob* aBlob) = 0;
+                                         Blob* aBlob) = 0;
 
   /**
    * Reports whether the instance supports AddIsindex().
@@ -106,11 +106,12 @@ protected:
    * @param aCharset the charset of the form as a string
    * @param aOriginatingElement the originating element (can be null)
    */
-  nsFormSubmission(const nsACString& aCharset, nsIContent* aOriginatingElement)
+  HTMLFormSubmission(const nsACString& aCharset,
+                     nsIContent* aOriginatingElement)
     : mCharset(aCharset)
     , mOriginatingElement(aOriginatingElement)
   {
-    MOZ_COUNT_CTOR(nsFormSubmission);
+    MOZ_COUNT_CTOR(HTMLFormSubmission);
   }
 
   // The name of the encoder charset
@@ -120,7 +121,7 @@ protected:
   nsCOMPtr<nsIContent> mOriginatingElement;
 };
 
-class nsEncodingFormSubmission : public nsFormSubmission
+class nsEncodingFormSubmission : public HTMLFormSubmission
 {
 public:
   nsEncodingFormSubmission(const nsACString& aCharset,
@@ -162,7 +163,7 @@ public:
   virtual nsresult AddNameValuePair(const nsAString& aName,
                                     const nsAString& aValue) override;
   virtual nsresult AddNameBlobOrNullPair(const nsAString& aName,
-                                         mozilla::dom::Blob* aBlob) override;
+                                         Blob* aBlob) override;
   virtual nsresult GetEncodedSubmission(nsIURI* aURI,
                                         nsIInputStream** aPostDataStream) override;
 
@@ -220,6 +221,9 @@ private:
  */
 nsresult GetSubmissionFromForm(nsGenericHTMLElement* aForm,
                                nsGenericHTMLElement* aOriginatingElement,
-                               nsFormSubmission** aFormSubmission);
+                               HTMLFormSubmission** aFormSubmission);
 
-#endif /* nsIFormSubmission_h___ */
+} // namespace dom
+} // namespace mozilla
+
+#endif /* mozilla_dom_HTMLFormSubmission_h */
diff --git a/dom/html/nsFormSubmissionConstants.h b/dom/html/HTMLFormSubmissionConstants.h
similarity index 84%
rename from dom/html/nsFormSubmissionConstants.h
rename to dom/html/HTMLFormSubmissionConstants.h
index 68baaa7eeb23..cedded9c6eff 100644
--- a/dom/html/nsFormSubmissionConstants.h
+++ b/dom/html/HTMLFormSubmissionConstants.h
@@ -4,14 +4,17 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-#ifndef nsFormSubmissionConstants_h__
-#define nsFormSubmissionConstants_h__
+#ifndef mozilla_dom_HTMLFormSubmissionConstants_h
+#define mozilla_dom_HTMLFormSubmissionConstants_h
+
+#include "nsIForm.h"
 
 static const nsAttrValue::EnumTable kFormMethodTable[] = {
   { "get", NS_FORM_METHOD_GET },
   { "post", NS_FORM_METHOD_POST },
   { 0 }
 };
+
 // Default method is 'get'.
 static const nsAttrValue::EnumTable* kFormDefaultMethod = &kFormMethodTable[0];
 
@@ -21,8 +24,8 @@ static const nsAttrValue::EnumTable kFormEnctypeTable[] = {
   { "text/plain", NS_FORM_ENCTYPE_TEXTPLAIN },
   { 0 }
 };
+
 // Default method is 'application/x-www-form-urlencoded'.
 static const nsAttrValue::EnumTable* kFormDefaultEnctype = &kFormEnctypeTable[1];
 
-#endif // nsFormSubmissionConstants_h__
-
+#endif // mozilla_dom_HTMLFormSubmissionConstants_h
diff --git a/dom/html/HTMLInputElement.cpp b/dom/html/HTMLInputElement.cpp
index 16256efc3d74..067a6f0c2cc3 100644
--- a/dom/html/HTMLInputElement.cpp
+++ b/dom/html/HTMLInputElement.cpp
@@ -11,6 +11,7 @@
 #include "mozilla/DebugOnly.h"
 #include "mozilla/dom/Date.h"
 #include "mozilla/dom/Directory.h"
+#include "mozilla/dom/HTMLFormSubmission.h"
 #include "mozilla/dom/FileSystemUtils.h"
 #include "nsAttrValueInlines.h"
 #include "nsCRTGlue.h"
@@ -21,6 +22,7 @@
 #include "nsIRadioVisitor.h"
 #include "nsIPhonetic.h"
 
+#include "HTMLFormSubmissionConstants.h"
 #include "mozilla/Telemetry.h"
 #include "nsIControllers.h"
 #include "nsIStringBundle.h"
@@ -38,9 +40,6 @@
 #include "nsPresContext.h"
 #include "nsMappedAttributes.h"
 #include "nsIFormControl.h"
-#include "nsIForm.h"
-#include "nsFormSubmission.h"
-#include "nsFormSubmissionConstants.h"
 #include "nsIDocument.h"
 #include "nsIPresShell.h"
 #include "nsIFormControlFrame.h"
@@ -6182,7 +6181,7 @@ HTMLInputElement::Reset()
 }
 
 NS_IMETHODIMP
-HTMLInputElement::SubmitNamesValues(nsFormSubmission* aFormSubmission)
+HTMLInputElement::SubmitNamesValues(HTMLFormSubmission* aFormSubmission)
 {
   // Disabled elements don't submit
   // For type=reset, and type=button, we just never submit, period.
diff --git a/dom/html/HTMLInputElement.h b/dom/html/HTMLInputElement.h
index b9154328e8aa..a9841763ed2f 100644
--- a/dom/html/HTMLInputElement.h
+++ b/dom/html/HTMLInputElement.h
@@ -154,7 +154,7 @@ public:
   // Overriden nsIFormControl methods
   NS_IMETHOD_(uint32_t) GetType() const override { return mType; }
   NS_IMETHOD Reset() override;
-  NS_IMETHOD SubmitNamesValues(nsFormSubmission* aFormSubmission) override;
+  NS_IMETHOD SubmitNamesValues(HTMLFormSubmission* aFormSubmission) override;
   NS_IMETHOD SaveState() override;
   virtual bool RestoreState(nsPresState* aState) override;
   virtual bool AllowDrop() override;
diff --git a/dom/html/HTMLObjectElement.cpp b/dom/html/HTMLObjectElement.cpp
index 2a551865ccde..a23fc193e8d1 100644
--- a/dom/html/HTMLObjectElement.cpp
+++ b/dom/html/HTMLObjectElement.cpp
@@ -5,6 +5,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "mozilla/EventStates.h"
+#include "mozilla/dom/HTMLFormSubmission.h"
 #include "mozilla/dom/HTMLObjectElement.h"
 #include "mozilla/dom/HTMLObjectElementBinding.h"
 #include "mozilla/dom/ElementInlines.h"
@@ -14,7 +15,6 @@
 #include "nsIDocument.h"
 #include "nsIPluginDocument.h"
 #include "nsIDOMDocument.h"
-#include "nsFormSubmission.h"
 #include "nsIObjectFrame.h"
 #include "nsNPAPIPluginInstance.h"
 #include "nsIWidget.h"
@@ -407,7 +407,7 @@ HTMLObjectElement::Reset()
 }
 
 NS_IMETHODIMP
-HTMLObjectElement::SubmitNamesValues(nsFormSubmission *aFormSubmission)
+HTMLObjectElement::SubmitNamesValues(HTMLFormSubmission *aFormSubmission)
 {
   nsAutoString name;
   if (!GetAttr(kNameSpaceID_None, nsGkAtoms::name, name)) {
diff --git a/dom/html/HTMLObjectElement.h b/dom/html/HTMLObjectElement.h
index 8f601349859b..a5bfb7ebf54b 100644
--- a/dom/html/HTMLObjectElement.h
+++ b/dom/html/HTMLObjectElement.h
@@ -16,6 +16,8 @@
 namespace mozilla {
 namespace dom {
 
+class HTMLFormSubmission;
+
 class HTMLObjectElement final : public nsGenericHTMLFormElement
                               , public nsObjectLoadingContent
                               , public nsIDOMHTMLObjectElement
@@ -70,7 +72,7 @@ public:
   }
 
   NS_IMETHOD Reset() override;
-  NS_IMETHOD SubmitNamesValues(nsFormSubmission *aFormSubmission) override;
+  NS_IMETHOD SubmitNamesValues(HTMLFormSubmission *aFormSubmission) override;
 
   virtual bool IsDisabled() const override { return false; }
 
diff --git a/dom/html/HTMLOptionsCollection.cpp b/dom/html/HTMLOptionsCollection.cpp
index 1fce684aedb3..294493c0c3f2 100644
--- a/dom/html/HTMLOptionsCollection.cpp
+++ b/dom/html/HTMLOptionsCollection.cpp
@@ -10,12 +10,12 @@
 #include "mozAutoDocUpdate.h"
 #include "mozilla/dom/BindingUtils.h"
 #include "mozilla/dom/Element.h"
+#include "mozilla/dom/HTMLFormSubmission.h"
 #include "mozilla/dom/HTMLOptionElement.h"
 #include "mozilla/dom/HTMLOptionsCollectionBinding.h"
 #include "mozilla/dom/HTMLSelectElement.h"
 #include "nsContentCreatorFunctions.h"
 #include "nsError.h"
-#include "nsFormSubmission.h"
 #include "nsGkAtoms.h"
 #include "nsIComboboxControlFrame.h"
 #include "nsIDocument.h"
diff --git a/dom/html/HTMLOutputElement.cpp b/dom/html/HTMLOutputElement.cpp
index a5c5c9d2cf48..17608c94fd0a 100644
--- a/dom/html/HTMLOutputElement.cpp
+++ b/dom/html/HTMLOutputElement.cpp
@@ -9,10 +9,10 @@
 #include "mozAutoDocUpdate.h"
 #include "mozilla/EventStates.h"
 #include "mozilla/dom/HTMLFormElement.h"
+#include "mozilla/dom/HTMLFormSubmission.h"
 #include "mozilla/dom/HTMLOutputElementBinding.h"
 #include "nsContentUtils.h"
 #include "nsDOMTokenList.h"
-#include "nsFormSubmission.h"
 
 NS_IMPL_NS_NEW_HTML_ELEMENT_CHECK_PARSER(Output)
 
@@ -75,7 +75,7 @@ HTMLOutputElement::Reset()
 }
 
 NS_IMETHODIMP
-HTMLOutputElement::SubmitNamesValues(nsFormSubmission* aFormSubmission)
+HTMLOutputElement::SubmitNamesValues(HTMLFormSubmission* aFormSubmission)
 {
   // The output element is not submittable.
   return NS_OK;
diff --git a/dom/html/HTMLOutputElement.h b/dom/html/HTMLOutputElement.h
index b9e6ecd9c4aa..5882624806d4 100644
--- a/dom/html/HTMLOutputElement.h
+++ b/dom/html/HTMLOutputElement.h
@@ -15,6 +15,8 @@
 namespace mozilla {
 namespace dom {
 
+class HTMLFormSubmission;
+
 class HTMLOutputElement final : public nsGenericHTMLFormElement,
                                 public nsStubMutationObserver,
                                 public nsIConstraintValidation
@@ -31,7 +33,7 @@ public:
   // nsIFormControl
   NS_IMETHOD_(uint32_t) GetType() const override { return NS_FORM_OUTPUT; }
   NS_IMETHOD Reset() override;
-  NS_IMETHOD SubmitNamesValues(nsFormSubmission* aFormSubmission) override;
+  NS_IMETHOD SubmitNamesValues(HTMLFormSubmission* aFormSubmission) override;
 
   virtual bool IsDisabled() const override { return false; }
 
diff --git a/dom/html/HTMLSelectElement.cpp b/dom/html/HTMLSelectElement.cpp
index ca37eb0622ac..b46a7c1a535f 100644
--- a/dom/html/HTMLSelectElement.cpp
+++ b/dom/html/HTMLSelectElement.cpp
@@ -12,6 +12,7 @@
 #include "mozilla/EventDispatcher.h"
 #include "mozilla/EventStates.h"
 #include "mozilla/dom/Element.h"
+#include "mozilla/dom/HTMLFormSubmission.h"
 #include "mozilla/dom/HTMLOptGroupElement.h"
 #include "mozilla/dom/HTMLOptionElement.h"
 #include "mozilla/dom/HTMLSelectElementBinding.h"
@@ -19,7 +20,6 @@
 #include "nsContentCreatorFunctions.h"
 #include "nsContentList.h"
 #include "nsError.h"
-#include "nsFormSubmission.h"
 #include "nsGkAtoms.h"
 #include "nsIComboboxControlFrame.h"
 #include "nsIDocument.h"
@@ -1656,7 +1656,7 @@ HTMLSelectElement::Reset()
 static NS_DEFINE_CID(kFormProcessorCID, NS_FORMPROCESSOR_CID);
 
 NS_IMETHODIMP
-HTMLSelectElement::SubmitNamesValues(nsFormSubmission* aFormSubmission)
+HTMLSelectElement::SubmitNamesValues(HTMLFormSubmission* aFormSubmission)
 {
   // Disabled elements don't submit
   if (IsDisabled()) {
diff --git a/dom/html/HTMLSelectElement.h b/dom/html/HTMLSelectElement.h
index 731aba3d7e0f..cce8eafabe0c 100644
--- a/dom/html/HTMLSelectElement.h
+++ b/dom/html/HTMLSelectElement.h
@@ -33,6 +33,7 @@ class EventChainPreVisitor;
 
 namespace dom {
 
+class HTMLFormSubmission;
 class HTMLSelectElement;
 
 #define NS_SELECT_STATE_IID                        \
@@ -289,7 +290,7 @@ public:
   // Overriden nsIFormControl methods
   NS_IMETHOD_(uint32_t) GetType() const override { return NS_FORM_SELECT; }
   NS_IMETHOD Reset() override;
-  NS_IMETHOD SubmitNamesValues(nsFormSubmission* aFormSubmission) override;
+  NS_IMETHOD SubmitNamesValues(HTMLFormSubmission* aFormSubmission) override;
   NS_IMETHOD SaveState() override;
   virtual bool RestoreState(nsPresState* aState) override;
   virtual bool IsDisabledForEvents(EventMessage aMessage) override;
diff --git a/dom/html/HTMLTextAreaElement.cpp b/dom/html/HTMLTextAreaElement.cpp
index f6114a99169e..0d216a3d0ed5 100644
--- a/dom/html/HTMLTextAreaElement.cpp
+++ b/dom/html/HTMLTextAreaElement.cpp
@@ -9,6 +9,7 @@
 #include "mozAutoDocUpdate.h"
 #include "mozilla/AsyncEventDispatcher.h"
 #include "mozilla/Attributes.h"
+#include "mozilla/dom/HTMLFormSubmission.h"
 #include "mozilla/dom/HTMLTextAreaElementBinding.h"
 #include "mozilla/EventDispatcher.h"
 #include "mozilla/EventStates.h"
@@ -18,7 +19,6 @@
 #include "nsContentCreatorFunctions.h"
 #include "nsError.h"
 #include "nsFocusManager.h"
-#include "nsFormSubmission.h"
 #include "nsIComponentManager.h"
 #include "nsIConstraintValidation.h"
 #include "nsIControllers.h"
@@ -1040,7 +1040,7 @@ HTMLTextAreaElement::Reset()
 }
 
 NS_IMETHODIMP
-HTMLTextAreaElement::SubmitNamesValues(nsFormSubmission* aFormSubmission)
+HTMLTextAreaElement::SubmitNamesValues(HTMLFormSubmission* aFormSubmission)
 {
   // Disabled elements don't submit
   if (IsDisabled()) {
diff --git a/dom/html/HTMLTextAreaElement.h b/dom/html/HTMLTextAreaElement.h
index c9b222e9a42d..283fcf7524f2 100644
--- a/dom/html/HTMLTextAreaElement.h
+++ b/dom/html/HTMLTextAreaElement.h
@@ -21,7 +21,6 @@
 
 #include "nsTextEditorState.h"
 
-class nsFormSubmission;
 class nsIControllers;
 class nsIDocument;
 class nsPresContext;
@@ -35,6 +34,8 @@ class EventStates;
 
 namespace dom {
 
+class HTMLFormSubmission;
+
 class HTMLTextAreaElement final : public nsGenericHTMLFormElementWithState,
                                   public nsIDOMHTMLTextAreaElement,
                                   public nsITextControlElement,
@@ -72,7 +73,7 @@ public:
   // nsIFormControl
   NS_IMETHOD_(uint32_t) GetType() const override { return NS_FORM_TEXTAREA; }
   NS_IMETHOD Reset() override;
-  NS_IMETHOD SubmitNamesValues(nsFormSubmission* aFormSubmission) override;
+  NS_IMETHOD SubmitNamesValues(HTMLFormSubmission* aFormSubmission) override;
   NS_IMETHOD SaveState() override;
   virtual bool RestoreState(nsPresState* aState) override;
   virtual bool IsDisabledForEvents(EventMessage aMessage) override;
diff --git a/dom/html/moz.build b/dom/html/moz.build
index 67072fb01721..3389e5abb12f 100644
--- a/dom/html/moz.build
+++ b/dom/html/moz.build
@@ -28,7 +28,6 @@ XPIDL_SOURCES += [
 XPIDL_MODULE = 'content_html'
 
 EXPORTS += [
-    'nsFormSubmission.h',
     'nsGenericHTMLElement.h',
     'nsHTMLDNSPrefetch.h',
     'nsIConstraintValidation.h',
@@ -61,6 +60,7 @@ EXPORTS.mozilla.dom += [
     'HTMLFontElement.h',
     'HTMLFormControlsCollection.h',
     'HTMLFormElement.h',
+    'HTMLFormSubmission.h',
     'HTMLFrameElement.h',
     'HTMLFrameSetElement.h',
     'HTMLHeadingElement.h',
@@ -140,6 +140,7 @@ UNIFIED_SOURCES += [
     'HTMLFontElement.cpp',
     'HTMLFormControlsCollection.cpp',
     'HTMLFormElement.cpp',
+    'HTMLFormSubmission.cpp',
     'HTMLFrameElement.cpp',
     'HTMLFrameSetElement.cpp',
     'HTMLHeadingElement.cpp',
@@ -195,7 +196,6 @@ UNIFIED_SOURCES += [
     'MediaError.cpp',
     'nsBrowserElement.cpp',
     'nsDOMStringMap.cpp',
-    'nsFormSubmission.cpp',
     'nsGenericHTMLElement.cpp',
     'nsGenericHTMLFrameElement.cpp',
     'nsHTMLContentSink.cpp',
diff --git a/dom/html/nsIFormControl.h b/dom/html/nsIFormControl.h
index 2d9283165922..d4f491a9c1d7 100644
--- a/dom/html/nsIFormControl.h
+++ b/dom/html/nsIFormControl.h
@@ -11,12 +11,12 @@
 
 class nsIDOMHTMLFormElement;
 class nsPresState;
-class nsFormSubmission;
 
 namespace mozilla {
 namespace dom {
 class Element;
 class HTMLFieldSetElement;
+class HTMLFormSubmission;
 } // namespace dom
 } // namespace mozilla
 
@@ -141,7 +141,8 @@ public:
    * @param aFormSubmission the form submission to notify of names/values/files
    *                       to submit
    */
-  NS_IMETHOD SubmitNamesValues(nsFormSubmission* aFormSubmission) = 0;
+  NS_IMETHOD
+  SubmitNamesValues(mozilla::dom::HTMLFormSubmission* aFormSubmission) = 0;
 
   /**
    * Save to presentation state.  The form control will determine whether it