Phase II Step 3: Reload LoFi/placeholder images via new ImageResource

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

Index: third_party/WebKit/Source/core/loader/resource/MockImageResourceClient.h
diff --git a/third_party/WebKit/Source/core/loader/resource/MockImageResourceClient.h b/third_party/WebKit/Source/core/loader/resource/MockImageResourceClient.h
index 9a16d55df7e8241cc953eaea57804d82d401f5d1..e3b35c2b7f97a10abf521ef95c7fbccc688601dc 100644
--- a/third_party/WebKit/Source/core/loader/resource/MockImageResourceClient.h
+++ b/third_party/WebKit/Source/core/loader/resource/MockImageResourceClient.h
@@ -12,6 +12,8 @@
 
 namespace blink {
 
+// MockImageResourceClient isn't re-registered to the new ImageResource
+// in LoFi image reloading.

[Nate Chapin, 2016/12/28 00:14:58]

This seems like it's going to trip someone up at some point in the future...

[hiroshige, 2017/01/25 02:01:49]

I replaced MockImageResourceClient with MockImageResourceObserver and makes the
tests observer-based in https://codereview.chromium.org/2607023002, so this
comment no longer applies (and is deleted).

 class MockImageResourceClient final : public MockResourceClient,
                                       public ImageResourceObserver {
  public:
@@ -25,7 +27,7 @@ class MockImageResourceClient final : public MockResourceClient,
 
   bool notifyFinishedCalled() const override;
 
-  void removeAsClient() override;
+  void removeAsClientAndObserver();
   void dispose() override;
 
   int imageChangedCount() const { return m_imageChangedCount; }
@@ -38,11 +40,17 @@ class MockImageResourceClient final : public MockResourceClient,
     return m_encodedSizeOnImageNotifyFinished;
   }
 
+  DEFINE_INLINE_VIRTUAL_TRACE() {
+    visitor->trace(m_content);
+    MockResourceClient::trace(visitor);
+  }
+
  private:
   int m_imageChangedCount;
   size_t m_encodedSizeOnLastImageChanged;
   int m_imageNotifyFinishedCount;
   size_t m_encodedSizeOnImageNotifyFinished;
+  Member<ImageResourceContent> m_content;
 };
 
 }  // namespace blink