Eliminate copies of encoded image data

third_party/WebKit/Source/web/ImageDecodeBench.cpp

Index: third_party/WebKit/Source/web/ImageDecodeBench.cpp
diff --git a/third_party/WebKit/Source/web/ImageDecodeBench.cpp b/third_party/WebKit/Source/web/ImageDecodeBench.cpp
index 6c8ecc1aa7af9bdd100705426c395f9ff6a08b29..375a7be51362fc53f379bfb426d557a7bf5cbddd 100644
--- a/third_party/WebKit/Source/web/ImageDecodeBench.cpp
+++ b/third_party/WebKit/Source/web/ImageDecodeBench.cpp
@@ -23,6 +23,7 @@ http://crbug.com/398235#c103 and http://crbug.com/258324#c5
 
 #include "platform/SharedBuffer.h"
 #include "platform/image-decoders/ImageDecoder.h"
+#include "platform/image-decoders/SharedBufferSegmentReader.h"
 #include "platform/testing/TestingPlatformSupport.h"
 #include "public/platform/Platform.h"
 #include "public/web/WebKit.h"
@@ -266,13 +267,14 @@ PassRefPtr<SharedBuffer> readFile(const char* fileName)
 
 bool decodeImageData(SharedBuffer* data, bool colorCorrection, size_t packetSize)
 {
-    OwnPtr<ImageDecoder> decoder = ImageDecoder::create(*data,
+    RefPtr<SharedBufferSegmentReader> segmentReader = adoptRef(new SharedBufferSegmentReader(data));
+    OwnPtr<ImageDecoder> decoder = ImageDecoder::create(*segmentReader.get(),
         ImageDecoder::AlphaPremultiplied, colorCorrection ?
             ImageDecoder::GammaAndColorProfileApplied : ImageDecoder::GammaAndColorProfileIgnored);
 
     if (!packetSize) {
         bool allDataReceived = true;
-        decoder->setData(data, allDataReceived);
+        decoder->setData(segmentReader.get(), allDataReceived);
 
         int frameCount = decoder->frameCount();
         for (int i = 0; i < frameCount; ++i) {
@@ -284,6 +286,7 @@ bool decodeImageData(SharedBuffer* data, bool colorCorrection, size_t packetSize
     }
 
     RefPtr<SharedBuffer> packetData = SharedBuffer::create();
+    segmentReader = adoptRef(new SharedBufferSegmentReader(packetData));
     unsigned position = 0;
     while (true) {
         const char* packet;
@@ -294,7 +297,7 @@ bool decodeImageData(SharedBuffer* data, bool colorCorrection, size_t packetSize
         position += length;
 
         bool allDataReceived = position == data->size();
-        decoder->setData(packetData.get(), allDataReceived);
+        decoder->setData(segmentReader.get(), allDataReceived);
 
         int frameCount = decoder->frameCount();
         for (int i = 0; i < frameCount; ++i) {