ImageResource: Reset the encoded image size after receiving all data

third_party/WebKit/Source/core/fetch/Resource.h

Index: third_party/WebKit/Source/core/fetch/Resource.h
diff --git a/third_party/WebKit/Source/core/fetch/Resource.h b/third_party/WebKit/Source/core/fetch/Resource.h
index a338bfac11e916a0606fab3c231438dd23edd395..7aae33e8c09fb14c5ef5661ebc03d7bdf0a12c90 100644
--- a/third_party/WebKit/Source/core/fetch/Resource.h
+++ b/third_party/WebKit/Source/core/fetch/Resource.h
@@ -169,7 +169,21 @@ class CORE_EXPORT Resource : public GarbageCollectedFinalized<Resource>,
   void setStatus(Status status) { m_status = status; }
 
   size_t size() const { return encodedSize() + decodedSize() + overheadSize(); }
+
+  // Returns the size of content (response body) before decoding. Adding a new
+  // usage of this function is not recommended (See the TODO below).
+  //
+  // TODO(hiroshige): Now encodedSize/decodedSize states are inconsistent and
+  // need to be refactored (crbug/643135).
   size_t encodedSize() const { return m_encodedSize; }
+
+  // Returns the current memory usage for the encoded data. Adding a new usage
+  // of this function is not recommended as the same reason as |encodedSize()|.
+  //
+  // |encodedSize()| and |encodedSizeMemoryUsage()| can return different values,
+  // e.g., when ImageResource purges encoded image data after finishing loading.
+  size_t encodedSizeMemoryUsage() const { return m_encodedSizeMemoryUsage; }
+
   size_t decodedSize() const { return m_decodedSize; }
   size_t overheadSize() const { return m_overheadSize; }
 
@@ -319,6 +333,7 @@ class CORE_EXPORT Resource : public GarbageCollectedFinalized<Resource>,
   virtual void destroyDecodedDataForFailedRevalidation() {}
 
   void setEncodedSize(size_t);
+  void setEncodedSizeMemoryUsage(size_t);
   void setDecodedSize(size_t);
   void didAccessDecodedData();
 
@@ -401,6 +416,7 @@ class CORE_EXPORT Resource : public GarbageCollectedFinalized<Resource>,
   unsigned long m_identifier;
 
   size_t m_encodedSize;
+  size_t m_encodedSizeMemoryUsage;
   size_t m_decodedSize;
 
   // Resource::calculateOverheadSize() is affected by changes in