Remove duplication of encoded image data

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

Index: third_party/WebKit/Source/platform/graphics/BitmapImage.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/BitmapImage.cpp b/third_party/WebKit/Source/platform/graphics/BitmapImage.cpp
index 17d815c5049c96f11bf0829b3427eecc716e092f..501c1d522a9f84ba0c94ff7b58e8ab5fb7a36b3e 100644
--- a/third_party/WebKit/Source/platform/graphics/BitmapImage.cpp
+++ b/third_party/WebKit/Source/platform/graphics/BitmapImage.cpp
@@ -118,6 +118,11 @@ void BitmapImage::destroyDecodedData()
     notifyMemoryChanged();
 }
 
+PassRefPtr<SharedBuffer> BitmapImage::data()
+{
+    return m_source.data();
+}
+
 void BitmapImage::notifyMemoryChanged()
 {
     if (getImageObserver())
@@ -184,6 +189,19 @@ bool BitmapImage::getHotSpot(IntPoint& hotSpot) const
     return m_source.getHotSpot(hotSpot);
 }
 
+bool BitmapImage::setData(PassRefPtr<SharedBuffer> data, bool allDataReceived)
+{
+    m_temporaryEncodedImageData = data;

[f(malita), 2016/07/08 15:34:40]

Do we need m_temporaryEncodedImageData at all?  Looks like we only set it
temporarily here, and dataChanged always clears it.

Why not set the source data upfront, before calling dataChanged() - i.e. would
this work:

bool BitmapImage::setData(PassRefPtr<SharedBuffer> data, bool allDataReceived)
{
    if (!data || data->isEmpty())
        return true;

    m_source.setData(*data, allDataReceived);

    return dataChanged(allDataReceived);
}

[hajimehoshi, 2016/07/11 06:15:07]

Done.

[f(malita), 2016/07/12 17:10:59]

Thanks, LGTM!

+    if (!m_temporaryEncodedImageData.get())
+        return true;
+
+    int length = m_temporaryEncodedImageData->size();
+    if (!length)
+        return true;
+
+    return dataChanged(allDataReceived);
+}
+
 bool BitmapImage::dataChanged(bool allDataReceived)
 {
     TRACE_EVENT0("blink", "BitmapImage::dataChanged");
@@ -218,8 +236,11 @@ bool BitmapImage::dataChanged(bool allDataReceived)
 
     // Feed all the data we've seen so far to the image decoder.
     m_allDataReceived = allDataReceived;
-    ASSERT(data());
-    m_source.setData(*data(), allDataReceived);
+    // |m_temporaryEncodedImageData| can be null only when testing.
+    if (m_temporaryEncodedImageData) {
+        m_source.setData(*m_temporaryEncodedImageData, allDataReceived);
+        m_temporaryEncodedImageData.clear();
+    }
 
     m_haveFrameCount = false;
     return isSizeAvailable();