Bug 1334247 - Add an explicit hook for the nsComboboxControlFrame case, and eliminate nsIAnonymousContentCreator::CreateFrameFor. r=bz

layout/base/nsCSSFrameConstructor.cpp

@@ -43,6 +43,7 @@
 #include "nsContainerFrame.h"
 #include "nsNameSpaceManager.h"
 #include "nsIComboboxControlFrame.h"
+#include "nsComboboxControlFrame.h"
 #include "nsIListControlFrame.h"
 #include "nsIDOMCharacterData.h"
 #include "nsPlaceholderFrame.h"
@@ -4124,10 +4125,7 @@ nsCSSFrameConstructor::CreateAnonymousFrames(nsFrameConstructorState& aState,
     ancestorPusher.PushStyleScope(aParent->AsElement());
   }
 
-  nsIAnonymousContentCreator* creator = do_QueryFrame(aParentFrame);
-  NS_ASSERTION(creator,
-               "How can that happen if we have nodes to construct frames for?");
-
+  nsComboboxControlFrame* comboboxFrame = do_QueryFrame(aParentFrame);
   InsertionPoint insertion(aParentFrame, aParent);
   for (uint32_t i=0; i < count; i++) {
     nsIContent* content = newAnonymousItems[i].mContent;
@@ -4138,12 +4136,15 @@ nsCSSFrameConstructor::CreateAnonymousFrames(nsFrameConstructorState& aState,
                  "nsIAnonymousContentCreator::CreateAnonymousContent to "
                  "output a list where the items have their own children");
 
-    nsIFrame* newFrame = creator->CreateFrameFor(content);
-    if (newFrame) {
-      NS_ASSERTION(content->GetPrimaryFrame(),
-                   "Content must have a primary frame now");
-      newFrame->AddStateBits(NS_FRAME_ANONYMOUSCONTENTCREATOR_CONTENT);
-      aChildItems.AddChild(newFrame);
+    if (comboboxFrame && comboboxFrame->GetDisplayNode() == content) {
+      // Combo box frames have a custom hook to create frames for the anonymous
+      // text node. This is the last vestigial trace of an old custom hook that
+      // allowed arbitrary custom frame creation by any nsIAnonymousContentCreator
+      // implementation. It's possible that this could all be refactored away.
+      nsIFrame* customFrame = comboboxFrame->CreateFrameForDisplayNode();
+      MOZ_ASSERT(customFrame);
+      customFrame->AddStateBits(NS_FRAME_ANONYMOUSCONTENTCREATOR_CONTENT);
+      aChildItems.AddChild(customFrame);
     } else {
       FrameConstructionItemList items;
       {
@@ -10706,13 +10707,6 @@ nsCSSFrameConstructor::AddFCItemsForAnonymousContent(
 {
   for (uint32_t i = 0; i < aAnonymousItems.Length(); ++i) {
     nsIContent* content = aAnonymousItems[i].mContent;
-#ifdef DEBUG
-    nsIAnonymousContentCreator* creator = do_QueryFrame(aFrame);
-    NS_ASSERTION(!creator || !creator->CreateFrameFor(content),
-                 "If you need to use CreateFrameFor, you need to call "
-                 "CreateAnonymousFrames manually and not follow the standard "
-                 "ProcessChildren() codepath for this frame");
-#endif
     // Gecko-styled nodes should have no pending restyle flags.
     MOZ_ASSERT_IF(!content->IsStyledByServo(),
                   !content->IsElement() ||

layout/forms/nsComboboxControlFrame.cpp

@@ -249,6 +249,7 @@ nsComboboxControlFrame::~nsComboboxControlFrame()
 //--------------------------------------------------------------
 
 NS_QUERYFRAME_HEAD(nsComboboxControlFrame)
+  NS_QUERYFRAME_ENTRY(nsComboboxControlFrame)
   NS_QUERYFRAME_ENTRY(nsIComboboxControlFrame)
   NS_QUERYFRAME_ENTRY(nsIFormControlFrame)
   NS_QUERYFRAME_ENTRY(nsIAnonymousContentCreator)
@@ -1347,16 +1348,9 @@ nsComboboxDisplayFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
 }
 
 nsIFrame*
-nsComboboxControlFrame::CreateFrameFor(nsIContent*      aContent)
+nsComboboxControlFrame::CreateFrameForDisplayNode()
 {
-  NS_PRECONDITION(nullptr != aContent, "null ptr");
-
-  NS_ASSERTION(mDisplayContent, "mDisplayContent can't be null!");
-
-  if (mDisplayContent != aContent) {
-    // We only handle the frames for mDisplayContent here
-    return nullptr;
-  }
+  MOZ_ASSERT(mDisplayContent);
 
   // Get PresShell
   nsIPresShell *shell = PresContext()->PresShell();
@@ -1381,7 +1375,7 @@ nsComboboxControlFrame::CreateFrameFor(nsIContent*      aContent)
   nsIFrame* textFrame = NS_NewTextFrame(shell, textStyleContext);
 
   // initialize the text frame
-  textFrame->Init(aContent, mDisplayFrame, nullptr);
+  textFrame->Init(mDisplayContent, mDisplayFrame, nullptr);
   mDisplayContent->SetPrimaryFrame(textFrame);
 
   nsFrameList textList(textFrame, textFrame);

layout/forms/nsComboboxControlFrame.h

@@ -54,6 +54,7 @@ class nsComboboxControlFrame final : public nsBlockFrame,
   typedef mozilla::gfx::DrawTarget DrawTarget;
 
 public:
+  NS_DECL_QUERYFRAME_TARGET(nsComboboxControlFrame)
   friend nsContainerFrame* NS_NewComboboxControlFrame(nsIPresShell* aPresShell,
                                                       nsStyleContext* aContext,
                                                       nsFrameState aFlags);
@@ -69,7 +70,9 @@ public:
   virtual nsresult CreateAnonymousContent(nsTArray<ContentInfo>& aElements) override;
   virtual void AppendAnonymousContentTo(nsTArray<nsIContent*>& aElements,
                                         uint32_t aFilter) override;
-  virtual nsIFrame* CreateFrameFor(nsIContent* aContent) override;
+
+  nsIContent* GetDisplayNode() { return mDisplayContent; }
+  nsIFrame* CreateFrameForDisplayNode();
 
 #ifdef ACCESSIBILITY
   virtual mozilla::a11y::AccType AccessibleType() override;

layout/generic/nsIAnonymousContentCreator.h

@@ -72,14 +72,6 @@ public:
    */
   virtual void AppendAnonymousContentTo(nsTArray<nsIContent*>& aElements,
                                         uint32_t aFilter) = 0;
-
-  /**
-   * Implementations can override this method to create special frames for the
-   * anonymous content returned from CreateAnonymousContent.
-   * By default this method returns nullptr, which means the default frame
-   * is created.
-   */
-  virtual nsIFrame* CreateFrameFor(nsIContent* aContent) { return nullptr; }
 };
 
 #endif