Eliminate copies of encoded image data

third_party/WebKit/Source/platform/graphics/gpu/WebGLImageConversion.cpp

Index: third_party/WebKit/Source/platform/graphics/gpu/WebGLImageConversion.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/gpu/WebGLImageConversion.cpp b/third_party/WebKit/Source/platform/graphics/gpu/WebGLImageConversion.cpp
index 94ed96346338b246a361d940987693eda8a377da..7eea9d0d0a7f6679f9a518dde94d323748794130 100644
--- a/third_party/WebKit/Source/platform/graphics/gpu/WebGLImageConversion.cpp
+++ b/third_party/WebKit/Source/platform/graphics/gpu/WebGLImageConversion.cpp
@@ -9,6 +9,7 @@
 #include "platform/graphics/cpu/arm/WebGLImageConversionNEON.h"
 #include "platform/graphics/cpu/x86/WebGLImageConversionSSE.h"
 #include "platform/image-decoders/ImageDecoder.h"
+#include "platform/image-decoders/SharedBufferSegmentReader.h"
 #include "third_party/skia/include/core/SkImage.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
@@ -2072,12 +2073,13 @@ void WebGLImageConversion::ImageExtractor::extractImage(bool premultiplyAlpha, b
 
     if ((!skiaImage || ignoreGammaAndColorProfile || (hasAlpha && !premultiplyAlpha)) && m_image->data()) {
         // Attempt to get raw unpremultiplied image data.
+        RefPtr<SharedBufferSegmentReader> segmentReader = adoptRef(new SharedBufferSegmentReader(m_image->data()));
         OwnPtr<ImageDecoder> decoder(ImageDecoder::create(
-            *(m_image->data()), ImageDecoder::AlphaNotPremultiplied,
+            *segmentReader.get(), ImageDecoder::AlphaNotPremultiplied,
             ignoreGammaAndColorProfile ? ImageDecoder::GammaAndColorProfileIgnored : ImageDecoder::GammaAndColorProfileApplied));
         if (!decoder)
             return;
-        decoder->setData(m_image->data(), true);
+        decoder->setData(segmentReader.get(), true);
         if (!decoder->frameCount())
             return;
         ImageFrame* frame = decoder->frameBufferAtIndex(0);