Fix FontFaceSet state getting stuck at loading

third_party/WebKit/Source/core/css/FontFaceSet.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 29 matching lines @@
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/style/StyleInheritedData.h"
 #include "platform/Histogram.h"
 
 namespace blink {
 
 static const int defaultFontSize = 10;
 static const char defaultFontFamily[] = "sans-serif";
 
-class LoadFontPromiseResolver final : public FontFace::LoadFontCallback {
+class LoadFontPromiseResolver final : public GarbageCollectedFinalized<LoadFontPromiseResolver>, public FontFace::LoadFontCallback {
+    USING_GARBAGE_COLLECTED_MIXIN(LoadFontPromiseResolver);
 public:
     static LoadFontPromiseResolver* create(FontFaceArray faces, ScriptState* scriptState)
     {
         return new LoadFontPromiseResolver(faces, scriptState);
     }
 
     void loadFonts(ExecutionContext*);
     ScriptPromise promise() { return m_resolver->promise(); }
 
     void notifyLoaded(FontFace*) override;
@@ skipping 150 matching lines @@
 {
     m_asyncRunner->stop();
 }
 
 void FontFaceSet::beginFontLoading(FontFace* fontFace)
 {
     m_histogram.incrementCount();
     addToLoadingFonts(fontFace);
 }
 
-void FontFaceSet::fontLoaded(FontFace* fontFace)
+void FontFaceSet::notifyLoaded(FontFace* fontFace)
 {
     m_histogram.updateStatus(fontFace);
     m_loadedFonts.append(fontFace);
     removeFromLoadingFonts(fontFace);
 }
 
-void FontFaceSet::loadError(FontFace* fontFace)
+void FontFaceSet::notifyError(FontFace* fontFace)
 {
     m_histogram.updateStatus(fontFace);
     m_failedFonts.append(fontFace);
     removeFromLoadingFonts(fontFace);
 }
 
 size_t FontFaceSet::approximateBlankCharacterCount() const
 {
     size_t count = 0;
     for (auto& fontFace : m_loadingFonts)
         count += fontFace->approximateBlankCharacterCount();
     return count;
 }
 
 void FontFaceSet::addToLoadingFonts(FontFace* fontFace)
 {
     if (!m_isLoading) {
         m_isLoading = true;
         m_shouldFireLoadingEvent = true;
         if (m_ready->getState() != ReadyProperty::Pending)
             m_ready->reset();
         handlePendingEventsAndPromisesSoon();
     }
     m_loadingFonts.add(fontFace);
+    fontFace->addCallback(this);
 }
 
 void FontFaceSet::removeFromLoadingFonts(FontFace* fontFace)
 {
     m_loadingFonts.remove(fontFace);
     if (m_loadingFonts.isEmpty())
         handlePendingEventsAndPromisesSoon();
 }
 
 ScriptPromise FontFaceSet::ready(ScriptState* scriptState)
@@ skipping 284 matching lines @@
 {
     visitor->trace(m_ready);
     visitor->trace(m_loadingFonts);
     visitor->trace(m_loadedFonts);
     visitor->trace(m_failedFonts);
     visitor->trace(m_nonCSSConnectedFaces);
     visitor->trace(m_asyncRunner);
     EventTargetWithInlineData::trace(visitor);
     Supplement<Document>::trace(visitor);
     ActiveDOMObject::trace(visitor);
+    FontFace::LoadFontCallback::trace(visitor);
 }
 
 } // namespace blink