Phase II Step 1: Remove updateImage() reentrancy around decodeError()

third_party/WebKit/Source/core/loader/resource/ImageResourceContent.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ImageResourceContent_h
 #define ImageResourceContent_h
 
 #include "core/CoreExport.h"
 #include "platform/geometry/IntRect.h"
 #include "platform/geometry/IntSizeHash.h"
@@ skipping 114 matching lines @@
     // Updates the image (including placeholder and decode error handling
     // and notifying observers) if needed.
     UpdateImage,
 
     // Clears the image and then updates the image if needed.
     ClearAndUpdateImage,
 
     // Clears the image and always notifies observers (without updating).
     ClearImageAndNotifyObservers,
   };
-  void updateImage(PassRefPtr<SharedBuffer>,
-                   UpdateImageOption,
-                   bool allDataReceived);
+  enum class UpdateImageResult {
+    NoDecodeError,
+
+    // Decode error occurred. Observers are not notified.
+    // Only occurs when UpdateImage or ClearAndUpdateImage is specified.
+    ShouldDecodeError,
+  };
+  WARN_UNUSED_RESULT UpdateImageResult updateImage(PassRefPtr<SharedBuffer>,
+                                                   UpdateImageOption,
+                                                   bool allDataReceived);
 
   void destroyDecodedData();
   void doResetAnimation();
 
   void setImageResourceInfo(ImageResourceInfo*);
 
   ResourcePriority priorityFromObservers() const;
   PassRefPtr<const SharedBuffer> resourceBuffer() const;
   bool shouldUpdateImageImmediately() const;
   bool hasObservers() const {
@@ skipping 26 matching lines @@
   RefPtr<blink::Image> m_image;
 
   HashCountedSet<ImageResourceObserver*> m_observers;
   HashCountedSet<ImageResourceObserver*> m_finishedObservers;
 
   Image::SizeAvailability m_sizeAvailable = Image::SizeUnavailable;
 
   // Indicates if this resource's encoded image data can be purged and refetched
   // from disk cache to save memory usage. See crbug/664437.
   bool m_isRefetchableDataFromDiskCache;
+
+#if DCHECK_IS_ON()
+  bool m_isUpdateImageBeingCalled = false;
+#endif
 };
 
 }  // namespace blink
 
 #endif