Bug 1909577 - Make some nsFocusManager::GetFocusedElement() users use its static version instead r=emilio,credential-management-reviewers,issammani

Now, we have `nsFocusManager::GetFocusedElementStatic()` which returns focused
element if the `nsFocusManager` instance is available.  Therefore, if
`nsFocusManager::GetFocusedElement()` users do not use other methods of
`nsFocusManager`, they can use `nsFocusManager::GetFocusedElementStatic()` and
make themselves simpler.

Note that some callers return early if `nsFocusManager` is not available, but
they do not return error and `nsFocusManager` instance is available in most
time of the life time of the process.  Therefore, we can simply stop using the
early return.

Differential Revision: https://phabricator.services.mozilla.com/D217527

accessible/ipc/RemoteAccessible.cpp

@@ -1877,15 +1877,12 @@ bool RemoteAccessible::HasPrimaryAction() const {
 
 void RemoteAccessible::TakeFocus() const {
   Unused << mDoc->SendTakeFocus(mID);
-  if (nsFocusManager* fm = nsFocusManager::GetFocusManager()) {
-    auto* bp = static_cast<dom::BrowserParent*>(mDoc->Manager());
-    MOZ_ASSERT(bp);
-    dom::Element* owner = bp->GetOwnerElement();
-    if (fm->GetFocusedElement() == owner) {
-      // This remote document tree is already focused. We don't need to do
-      // anything else.
-      return;
-    }
+  auto* bp = static_cast<dom::BrowserParent*>(mDoc->Manager());
+  MOZ_ASSERT(bp);
+  if (nsFocusManager::GetFocusedElementStatic() == bp->GetOwnerElement()) {
+    // This remote document tree is already focused. We don't need to do
+    // anything else.
+    return;
   }
   // Otherwise, we need to focus the <browser> or <iframe> element embedding the
   // remote document in the parent process. If `this` is in an OOP iframe, we

dom/base/Document.cpp

@@ -6087,12 +6087,11 @@ nsresult Document::TurnEditingOff() {
 
   // Editor resets selection since it is being destroyed.  But if focus is
   // still into editable control, we have to initialize selection again.
-  if (nsFocusManager* fm = nsFocusManager::GetFocusManager()) {
-    if (RefPtr<TextControlElement> textControlElement =
-            TextControlElement::FromNodeOrNull(fm->GetFocusedElement())) {
-      if (RefPtr<TextEditor> textEditor = textControlElement->GetTextEditor()) {
-        textEditor->ReinitializeSelection(*textControlElement);
-      }
+  if (RefPtr<TextControlElement> textControlElement =
+          TextControlElement::FromNodeOrNull(
+              nsFocusManager::GetFocusedElementStatic())) {
+    if (RefPtr<TextEditor> textEditor = textControlElement->GetTextEditor()) {
+      textEditor->ReinitializeSelection(*textControlElement);
     }
   }
 
@@ -6157,10 +6156,7 @@ nsresult Document::EditingStateChanged() {
     // Note that even if focusedElement is an editable text control element,
     // it becomes not editable from HTMLEditor point of view since text
     // control elements are manged by TextEditor.
-    RefPtr<Element> focusedElement =
-        nsFocusManager::GetFocusManager()
-            ? nsFocusManager::GetFocusManager()->GetFocusedElement()
-            : nullptr;
+    RefPtr<Element> focusedElement = nsFocusManager::GetFocusedElementStatic();
     DebugOnly<nsresult> rvIgnored =
         HTMLEditor::FocusedElementOrDocumentBecomesNotEditable(
             htmlEditor, *this, focusedElement);
@@ -6444,9 +6440,8 @@ void Document::ChangeContentEditableCount(Element* aElement, int32_t aChange) {
 }
 
 void Document::DeferredContentEditableCountChange(Element* aElement) {
-  const RefPtr<nsFocusManager> fm = nsFocusManager::GetFocusManager();
   const bool elementHasFocus =
-      aElement && fm && fm->GetFocusedElement() == aElement;
+      aElement && nsFocusManager::GetFocusedElementStatic() == aElement;
   if (elementHasFocus) {
     MOZ_ASSERT(nsContentUtils::IsSafeToRunScript());
     // When contenteditable of aElement is changed and HTMLEditor works with it
@@ -6522,7 +6517,7 @@ void Document::DeferredContentEditableCountChange(Element* aElement) {
   // having focus, the HTMLEditor won't receive `focus` event.  Therefore, we
   // need to notify HTMLEditor of it becomes editable.
   if (elementHasFocus && aElement->HasFlag(NODE_IS_EDITABLE) &&
-      fm->GetFocusedElement() == aElement) {
+      nsFocusManager::GetFocusedElementStatic() == aElement) {
     if (RefPtr<HTMLEditor> htmlEditor = GetHTMLEditor()) {
       DebugOnly<nsresult> rvIgnored =
           htmlEditor->FocusedElementOrDocumentBecomesEditable(*this, aElement);

dom/base/nsContentUtils.cpp

@@ -7044,13 +7044,6 @@ void* nsContentUtils::AllocClassMatchingInfo(nsINode* aRootNode,
   return info;
 }
 
-// static
-bool nsContentUtils::IsFocusedContent(const nsIContent* aContent) {
-  nsFocusManager* fm = nsFocusManager::GetFocusManager();
-
-  return fm && fm->GetFocusedElement() == aContent;
-}
-
 bool nsContentUtils::HasScrollgrab(nsIContent* aContent) {
   // If we ever standardize this feature we'll want to hook this up properly
   // again. For now we're removing all the DOM-side code related to it but

dom/base/nsContentUtils.h

@@ -2549,14 +2549,6 @@ class nsContentUtils {
   static mozilla::WindowRenderer* WindowRendererForContent(
       const nsIContent* aContent);
 
-  /**
-   * Determine whether a content node is focused or not,
-   *
-   * @param aContent the content node to check
-   * @return true if the content node is focused, false otherwise.
-   */
-  static bool IsFocusedContent(const nsIContent* aContent);
-
   /**
    * Returns true if calling execCommand with 'cut' or 'copy' arguments is
    * allowed for the given subject principal. These are only allowed if the user

dom/base/nsDOMWindowUtils.cpp

@@ -3078,12 +3078,7 @@ nsDOMWindowUtils::ZoomToFocusedInput() {
     return NS_OK;
   }
 
-  nsFocusManager* fm = nsFocusManager::GetFocusManager();
-  if (!fm) {
-    return NS_OK;
-  }
-
-  RefPtr<Element> element = fm->GetFocusedElement();
+  const RefPtr<Element> element = nsFocusManager::GetFocusedElementStatic();
   if (!element) {
     return NS_OK;
   }

dom/html/HTMLInputElement.cpp

@@ -3969,14 +3969,14 @@ nsresult HTMLInputElement::PostHandleEvent(EventChainPostVisitor& aVisitor) {
                 wheelEvent->mDeltaY != 0 &&
                 wheelEvent->mDeltaMode != WheelEvent_Binding::DOM_DELTA_PIXEL) {
               if (mType == FormControlType::InputNumber) {
-                if (nsContentUtils::IsFocusedContent(this)) {
+                if (nsFocusManager::GetFocusedElementStatic() == this) {
                   StepNumberControlForUserEvent(wheelEvent->mDeltaY > 0 ? -1
                                                                         : 1);
                   FireChangeEventIfNeeded();
                   aVisitor.mEvent->PreventDefault();
                 }
               } else if (mType == FormControlType::InputRange &&
-                         nsContentUtils::IsFocusedContent(this) &&
+                         nsFocusManager::GetFocusedElementStatic() == this &&
                          GetMinimum() < GetMaximum()) {
                 Decimal value = GetValueAsDecimal();
                 Decimal step = GetStep();

dom/html/TextControlState.cpp

@@ -15,6 +15,7 @@
 #include "nsCOMPtr.h"
 #include "nsView.h"
 #include "nsCaret.h"
+#include "nsFocusManager.h"
 #include "nsContentCreatorFunctions.h"
 #include "nsTextControlFrame.h"
 #include "nsIControllers.h"
@@ -858,7 +859,7 @@ void TextInputListener::OnSelectionChange(Selection& aSelection,
   mSelectionWasCollapsed = collapsed;
 
   if (!weakFrame.IsAlive() || !mFrame ||
-      !nsContentUtils::IsFocusedContent(mFrame->GetContent())) {
+      nsFocusManager::GetFocusedElementStatic() != mFrame->GetContent()) {
     return;
   }
 

editor/libeditor/EditorBase.cpp

@@ -5841,12 +5841,7 @@ Element* EditorBase::GetFocusedElement() const {
     return nullptr;
   }
 
-  nsFocusManager* focusManager = nsFocusManager::GetFocusManager();
-  if (NS_WARN_IF(!focusManager)) {
-    return nullptr;
-  }
-
-  Element* focusedElement = focusManager->GetFocusedElement();
+  Element* const focusedElement = nsFocusManager::GetFocusedElementStatic();
   MOZ_ASSERT((focusedElement == eventTarget) ==
              SameCOMIdentity(focusedElement, eventTarget));
 
@@ -5956,11 +5951,6 @@ bool EditorBase::CanKeepHandlingFocusEvent(
     return false;
   }
 
-  nsFocusManager* focusManager = nsFocusManager::GetFocusManager();
-  if (MOZ_UNLIKELY(!focusManager)) {
-    return false;
-  }
-
   // If the event target is document mode, we only need to handle the focus
   // event when the document is still in designMode.  Otherwise, the
   // mode has been disabled by somebody while we're handling the focus event.
@@ -5972,7 +5962,9 @@ bool EditorBase::CanKeepHandlingFocusEvent(
   // If nobody has focus, the focus event target has been blurred by somebody
   // else.  So the editor shouldn't initialize itself to start to handle
   // anything.
-  if (!focusManager->GetFocusedElement()) {
+  const Element* const focusedElement =
+      nsFocusManager::GetFocusedElementStatic();
+  if (!focusedElement) {
     return false;
   }
 
@@ -5992,7 +5984,7 @@ bool EditorBase::CanKeepHandlingFocusEvent(
       aOriginalEventTargetNode.AsContent()
           ->FindFirstNonChromeOnlyAccessContent();
   const nsIContent* exposedFocusedContent =
-      focusManager->GetFocusedElement()->FindFirstNonChromeOnlyAccessContent();
+      focusedElement->FindFirstNonChromeOnlyAccessContent();
   return exposedTargetContent && exposedFocusedContent &&
          exposedTargetContent == exposedFocusedContent;
 }

editor/libeditor/EditorEventListener.cpp

@@ -209,19 +209,15 @@ void EditorEventListener::Disconnect() {
   const OwningNonNull<EditorBase> editorBase = *mEditorBase;
   mEditorBase = nullptr;
 
-  nsFocusManager* fm = nsFocusManager::GetFocusManager();
-  if (fm) {
-    nsIContent* focusedContent = fm->GetFocusedElement();
-    mozilla::dom::Element* root = editorBase->GetRoot();
-    if (focusedContent && root &&
-        focusedContent->IsInclusiveDescendantOf(root)) {
-      // Reset the Selection ancestor limiter and SelectionController state
-      // that EditorBase::InitializeSelection set up.
-      DebugOnly<nsresult> rvIgnored = editorBase->FinalizeSelection();
-      NS_WARNING_ASSERTION(
-          NS_SUCCEEDED(rvIgnored),
-          "EditorBase::FinalizeSelection() failed, but ignored");
-    }
+  const Element* const focusedElement =
+      nsFocusManager::GetFocusedElementStatic();
+  mozilla::dom::Element* root = editorBase->GetRoot();
+  if (focusedElement && root && focusedElement->IsInclusiveDescendantOf(root)) {
+    // Reset the Selection ancestor limiter and SelectionController state
+    // that EditorBase::InitializeSelection set up.
+    DebugOnly<nsresult> rvIgnored = editorBase->FinalizeSelection();
+    NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
+                         "EditorBase::FinalizeSelection() failed, but ignored");
   }
 }
 

editor/libeditor/HTMLEditor.cpp

@@ -6894,12 +6894,7 @@ NS_IMETHODIMP HTMLEditor::SetWrapWidth(int32_t aWrapColumn) {
 }
 
 Element* HTMLEditor::GetFocusedElement() const {
-  nsFocusManager* focusManager = nsFocusManager::GetFocusManager();
-  if (NS_WARN_IF(!focusManager)) {
-    return nullptr;
-  }
-
-  Element* const focusedElement = focusManager->GetFocusedElement();
+  Element* const focusedElement = nsFocusManager::GetFocusedElementStatic();
 
   Document* document = GetDocument();
   if (NS_WARN_IF(!document)) {
@@ -7183,14 +7178,12 @@ nsINode* HTMLEditor::GetFocusedNode() const {
     return nullptr;
   }
 
-  // focusedElement might be non-null even focusManager->GetFocusedElement()
-  // is null.  That's the designMode case, and in that case our
-  // FocusedContent() returns the root element, but we want to return
-  // the document.
+  // focusedElement might be non-null even
+  // nsFocusManager::GetFocusedElementStatic() returns null.  That's the
+  // designMode case, and in that case our GetFocusedElement() returns the root
+  // element, but we want to return the document.
 
-  nsFocusManager* focusManager = nsFocusManager::GetFocusManager();
-  NS_ASSERTION(focusManager, "Focus manager is null");
-  if ((focusedElement = focusManager->GetFocusedElement())) {
+  if ((focusedElement = nsFocusManager::GetFocusedElementStatic())) {
     return focusedElement;
   }
 

editor/libeditor/TextEditor.cpp

@@ -772,15 +772,10 @@ nsresult TextEditor::OnFocus(const nsINode& aOriginalEventTargetNode) {
 
 nsresult TextEditor::OnBlur(const EventTarget* aEventTarget) {
   // check if something else is focused. If another element is focused, then
-  // we should not change the selection.
-  nsFocusManager* focusManager = nsFocusManager::GetFocusManager();
-  if (MOZ_UNLIKELY(!focusManager)) {
-    return NS_OK;
-  }
-
-  // If another element already has focus, we should not maintain the selection
-  // because we may not have the rights doing it.
-  if (focusManager->GetFocusedElement()) {
+  // we should not change the selection.  If another element already has focus,
+  // we should not maintain the selection because we may not have the rights
+  // doing it.
+  if (nsFocusManager::GetFocusedElementStatic()) {
     return NS_OK;
   }
 

layout/base/PresShell.cpp

@@ -9208,11 +9208,7 @@ bool PresShell::EventHandler::AdjustContextMenuKeyEvent(
   // If we're here because of the key-equiv for showing context menus, we
   // have to reset the event target to the currently focused element. Get it
   // from the focus controller.
-  RefPtr<Element> currentFocus;
-  nsFocusManager* fm = nsFocusManager::GetFocusManager();
-  if (fm) {
-    currentFocus = fm->GetFocusedElement();
-  }
+  RefPtr<Element> currentFocus = nsFocusManager::GetFocusedElementStatic();
 
   // Reset event coordinates relative to focused frame in view
   if (currentFocus) {

layout/forms/nsTextControlFrame.cpp

@@ -981,12 +981,12 @@ void nsTextControlFrame::HandleReadonlyOrDisabledChange() {
     return;
   }
   if (el->IsDisabledOrReadOnly()) {
-    if (nsContentUtils::IsFocusedContent(el)) {
+    if (nsFocusManager::GetFocusedElementStatic() == el) {
       selCon->SetCaretEnabled(false);
     }
     editor->AddFlags(nsIEditor::eEditorReadonlyMask);
   } else {
-    if (nsContentUtils::IsFocusedContent(el)) {
+    if (nsFocusManager::GetFocusedElementStatic() == el) {
       selCon->SetCaretEnabled(true);
     }
     editor->RemoveFlags(nsIEditor::eEditorReadonlyMask);

toolkit/components/satchel/nsFormFillController.cpp

@@ -249,17 +249,13 @@ nsFormFillController::MarkAsAutoCompletableField(HTMLInputElement* aInput) {
 
   aInput->EnablePreview();
 
-  nsFocusManager* fm = nsFocusManager::GetFocusManager();
-  if (fm) {
-    nsCOMPtr<nsIContent> focusedContent = fm->GetFocusedElement();
-    if (focusedContent == aInput) {
-      if (!mFocusedInput) {
-        MaybeStartControllingInput(aInput);
-      } else {
-        // See `MarkAsLoginManagerField` for why this is needed.
-        nsCOMPtr<nsIAutoCompleteController> controller = mController;
-        controller->ResetInternalState();
-      }
+  if (nsFocusManager::GetFocusedElementStatic() == aInput) {
+    if (!mFocusedInput) {
+      MaybeStartControllingInput(aInput);
+    } else {
+      // See `MarkAsLoginManagerField` for why this is needed.
+      nsCOMPtr<nsIAutoCompleteController> controller = mController;
+      controller->ResetInternalState();
     }
   }