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..47b364085b7224e83851190fef6a29383f747f66 100644
--- a/third_party/WebKit/Source/platform/graphics/BitmapImage.cpp
+++ b/third_party/WebKit/Source/platform/graphics/BitmapImage.cpp
@@ -118,6 +118,18 @@ void BitmapImage::destroyDecodedData()
     notifyMemoryChanged();
 }
 
+PassRefPtr<SharedBuffer> BitmapImage::data()
+{
+    if (PassRefPtr<SharedBuffer> data = cachedData())

[haraken, 2016/06/23 01:26:41]

PassRefPtr<SharedBuffer> => RefPtr<SharedBuffer>

[hajimehoshi, 2016/06/23 09:23:12]

Done.

+        return data;
+    return m_source.data();
+}
+
+PassRefPtr<SharedBuffer> BitmapImage::cachedData()
+{
+    return Image::data();
+}
+
 void BitmapImage::notifyMemoryChanged()
 {
     if (getImageObserver())
@@ -218,8 +230,13 @@ 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);
+    if (cachedData()) {
+        m_source.setData(*cachedData(), allDataReceived);
+        if (m_source.hasData()) {
+            resetEncodedImageData();

[haraken, 2016/06/23 01:26:40]

Add a comment and explain what this is doing and why it's important.

[hajimehoshi, 2016/06/23 09:23:13]

Done.

+            DCHECK(!cachedData());

[haraken, 2016/06/23 01:26:40]

Would it be clearer to rename cachedData to encodedImageData?

[hajimehoshi, 2016/06/23 09:23:13]

Hmm, I want to emphasize BitmapImage no longer has a cached encoded image data.
encodedImageData might be confusing. BTW resetEncodedImageData is also confusing
as the same reason, so I'll rename this.

+        }
+    }
 
     m_haveFrameCount = false;
     return isSizeAvailable();