Bug 1238160 - Set tab context's isolation from frame attr. r=smaug

Renames existing nsFrameLoader::OwnerIsBrowser* methods to add "Moz" prefix for
clarity.

Adds nsFrameLoader::OwnerIsIsolatedMozBrowserFrame which checks the noisolation
attribute of mozbrowser frames, if present.

This is used to set isolation in nsFrameLoader::GetNewTabContext only when true.

MozReview-Commit-ID: Dz02xBoKh1P

dom/html/nsGenericHTMLFrameElement.cpp

@@ -550,6 +550,20 @@ nsGenericHTMLFrameElement::GetReallyIsWidget(bool *aOut)
   return NS_OK;
 }
 
+/* [infallible] */ NS_IMETHODIMP
+nsGenericHTMLFrameElement::GetIsolated(bool *aOut)
+{
+  *aOut = true;
+
+  if (!nsContentUtils::IsSystemPrincipal(NodePrincipal())) {
+    return NS_OK;
+  }
+
+  // Isolation is only disabled if the attribute is present
+  *aOut = !HasAttr(kNameSpaceID_None, nsGkAtoms::noisolation);
+  return NS_OK;
+}
+
 /* [infallible] */ NS_IMETHODIMP
 nsGenericHTMLFrameElement::GetIsExpectingSystemMessage(bool *aOut)
 {
@@ -705,4 +719,3 @@ nsGenericHTMLFrameElement::SwapFrameLoaders(nsXULElement& aOtherOwner,
 {
   aError.Throw(NS_ERROR_NOT_IMPLEMENTED);
 }
-