Eliminate copies of encoded image data

third_party/WebKit/Source/platform/image-decoders/ImageDecoderTestHelpers.cpp

Index: third_party/WebKit/Source/platform/image-decoders/ImageDecoderTestHelpers.cpp
diff --git a/third_party/WebKit/Source/platform/image-decoders/ImageDecoderTestHelpers.cpp b/third_party/WebKit/Source/platform/image-decoders/ImageDecoderTestHelpers.cpp
index 10824940aad9179c0359a15481b7e693c43902bb..19fb93788204b3421686790246c1ba1888427470 100644
--- a/third_party/WebKit/Source/platform/image-decoders/ImageDecoderTestHelpers.cpp
+++ b/third_party/WebKit/Source/platform/image-decoders/ImageDecoderTestHelpers.cpp
@@ -7,6 +7,7 @@
 #include "platform/SharedBuffer.h"
 #include "platform/image-decoders/ImageDecoder.h"
 #include "platform/image-decoders/ImageFrame.h"
+#include "platform/image-decoders/SharedBufferSegmentReader.h"
 #include "platform/testing/UnitTestHelpers.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebUnitTestSupport.h"
@@ -42,7 +43,8 @@ unsigned hashBitmap(const SkBitmap& bitmap)
 static unsigned createDecodingBaseline(DecoderCreator createDecoder, SharedBuffer* data)
 {
     OwnPtr<ImageDecoder> decoder = createDecoder();
-    decoder->setData(data, true);
+    RefPtr<SharedBufferSegmentReader> segmentReader = adoptRef(new SharedBufferSegmentReader(data));
+    decoder->setData(segmentReader.get(), true);

[f(malita), 2016/03/23 16:41:58]

If we update setData to take a PassRefPtr, this should turn into
segmentReader.release().

Or inlined: setData(adoptRef(...)).

     ImageFrame* frame = decoder->frameBufferAtIndex(0);
     return hashBitmap(frame->bitmap());
 }
@@ -50,7 +52,8 @@ static unsigned createDecodingBaseline(DecoderCreator createDecoder, SharedBuffe
 void createDecodingBaseline(DecoderCreator createDecoder, SharedBuffer* data, Vector<unsigned>* baselineHashes)
 {
     OwnPtr<ImageDecoder> decoder = createDecoder();
-    decoder->setData(data, true);
+    RefPtr<SharedBufferSegmentReader> segmentReader = adoptRef(new SharedBufferSegmentReader(data));
+    decoder->setData(segmentReader.get(), true);

[f(malita), 2016/03/23 16:41:58]

ditto

     size_t frameCount = decoder->frameCount();
     for (size_t i = 0; i < frameCount; ++i) {
         ImageFrame* frame = decoder->frameBufferAtIndex(i);
@@ -74,13 +77,14 @@ void testByteByByteDecode(DecoderCreator createDecoder, const char* file, size_t
 
     // Pass data to decoder byte by byte.
     RefPtr<SharedBuffer> sourceData[2] = { SharedBuffer::create(), SharedBuffer::create() };
+    RefPtr<SharedBufferSegmentReader> segmentReader[2] = { adoptRef(new SharedBufferSegmentReader(sourceData[0])), adoptRef(new SharedBufferSegmentReader(sourceData[1])) };
     const char* source = data->data();
 
     for (size_t length = 1; length <= data->size() && !decoder->failed(); ++length) {
         sourceData[0]->append(source, 1);
         sourceData[1]->append(source++, 1);
         // Alternate the buffers to cover the JPEGImageDecoder::onSetData restart code.
-        decoder->setData(sourceData[length & 1].get(), length == data->size());
+        decoder->setData(segmentReader[length & 1].get(), length == data->size());
 
         EXPECT_LE(frameCount, decoder->frameCount());
         frameCount = decoder->frameCount();
@@ -125,7 +129,8 @@ void testMergeBuffer(DecoderCreator createDecoder, const char* file)
     segmentedData->append(data->data(), data->size());
 
     OwnPtr<ImageDecoder> decoder = createDecoder();
-    decoder->setData(segmentedData.get(), true);
+    RefPtr<SharedBufferSegmentReader> segmentReader = adoptRef(new SharedBufferSegmentReader(data));
+    decoder->setData(segmentReader.get(), true);
 
     ASSERT_TRUE(decoder->isSizeAvailable());