Remove duplication of encoded image data

third_party/WebKit/Source/platform/graphics/DeferredImageDecoder.cpp

Index: third_party/WebKit/Source/platform/graphics/DeferredImageDecoder.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/DeferredImageDecoder.cpp b/third_party/WebKit/Source/platform/graphics/DeferredImageDecoder.cpp
index 5600cc13cc12c8c73fd6a7088e16eafc53bf2852..969d0942f528d635ae80b32aa10fc9783ed558fe 100644
--- a/third_party/WebKit/Source/platform/graphics/DeferredImageDecoder.cpp
+++ b/third_party/WebKit/Source/platform/graphics/DeferredImageDecoder.cpp
@@ -117,6 +117,24 @@ PassRefPtr<SkImage> DeferredImageDecoder::createFrameAtIndex(size_t index)
     return adoptRef(SkImage::NewFromBitmap(frame->bitmap()));
 }
 
+bool DeferredImageDecoder::hasData() const
+{
+    return static_cast<bool>(m_rwBuffer);
+}
+
+PassRefPtr<SharedBuffer> DeferredImageDecoder::data()

[scroggo_chromium, 2016/06/20 19:00:43]

This method can be slow, especially if it's called regularly. Who calls it?

It looks like the stack trace would be:

ImageResource::resourceBuffer()
BitmapImage::data() (overriding Image::data())
ImageSource::data()

Does this get called often?

[hajimehoshi, 2016/06/22 09:42:29]

IIUC this is not called often: Resource::resourceBuffer() is called from
FrameSerializer, the inspector, tests, etc. The situation is limited.

+{
+    if (!m_rwBuffer)
+        return nullptr;
+    RefPtr<SkROBuffer> roBuffer = adoptRef(m_rwBuffer->newRBufferSnapshot());
+    RefPtr<SharedBuffer> sharedBuffer = SharedBuffer::create(roBuffer->size());
+    SkROBuffer::Iter it(roBuffer.get());
+    do {
+        sharedBuffer->append(static_cast<const char*>(it.data()), it.size());
+    } while (it.next());
+    return sharedBuffer;
+}
+
 void DeferredImageDecoder::setData(SharedBuffer& data, bool allDataReceived)
 {
     if (m_actualDecoder) {
@@ -131,8 +149,9 @@ void DeferredImageDecoder::setData(SharedBuffer& data, bool allDataReceived)
 
         const char* segment = 0;
         for (size_t length = data.getSomeData(segment, m_rwBuffer->size());
-            length; length = data.getSomeData(segment, m_rwBuffer->size()))
+            length; length = data.getSomeData(segment, m_rwBuffer->size())) {
             m_rwBuffer->append(segment, length);
+        }
     }
 }