Explicitly clear the image in the first updateImage() call

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

Index: third_party/WebKit/Source/core/loader/resource/ImageResource.h
diff --git a/third_party/WebKit/Source/core/loader/resource/ImageResource.h b/third_party/WebKit/Source/core/loader/resource/ImageResource.h
index 3872761ac4bf6f0448d118f47e8bff1a1a5c7a16..4e6fcede77f530b6511ca1791a6f91ba16096581 100644
--- a/third_party/WebKit/Source/core/loader/resource/ImageResource.h
+++ b/third_party/WebKit/Source/core/loader/resource/ImageResource.h
@@ -25,6 +25,7 @@
 
 #include "core/CoreExport.h"
 #include "core/fetch/Resource.h"
+#include "core/loader/resource/ImageResourceContent.h"
 #include "core/loader/resource/ImageResourceInfo.h"
 #include "core/loader/resource/MultipartImageResourceParser.h"
 #include "platform/Timer.h"
@@ -129,6 +130,12 @@ class CORE_EXPORT ImageResource final
   void destroyDecodedDataIfPossible() override;
   void destroyDecodedDataForFailedRevalidation() override;
 
+  // When UpdateImageOption is UpdateImage but this is the first
+  // updateImage() call, then ClearAndUpdateImage is used instead to enforce
+  // new image creation.
+  void updateImage(PassRefPtr<SharedBuffer>,
+                   ImageResourceContent::UpdateImageOption,
+                   bool allDataReceived);
   void flushImageIfNeeded(TimerBase*);
 
   bool shouldReloadBrokenPlaceholder() const {
@@ -139,6 +146,10 @@ class CORE_EXPORT ImageResource final
 
   Member<ImageResourceContent> m_content;
 
+  // Indicates we should clear the image (and then create a new image) in the
+  // next updateImage() call.
+  bool m_shouldEnforceClearImage = true;
+
   // TODO(hiroshige): move |m_devicePixelRatioHeaderValue| and
   // |m_hasDevicePixelRatioHeaderValue| to ImageResourceContent and update
   // it via ImageResourceContent::updateImage().