Pull up tests for WebP and GIF image decoders.

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

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "platform/image-decoders/ImageDecoder.h"
 #include "wtf/Vector.h"
 #include <memory>
 
 class SkBitmap;
 
 namespace blink {
 class ImageDecoder;
 class SharedBuffer;
 
 const char decodersTestingDir[] = "Source/platform/image-decoders/testing";
 
 using DecoderCreator = std::unique_ptr<ImageDecoder> (*)();
+using DecoderCreatorWithAlpha =
+    std::unique_ptr<ImageDecoder> (*)(ImageDecoder::AlphaOption);
+
 PassRefPtr<SharedBuffer> readFile(const char* fileName);
 PassRefPtr<SharedBuffer> readFile(const char* dir, const char* fileName);
 unsigned hashBitmap(const SkBitmap&);
 void createDecodingBaseline(DecoderCreator,
                             SharedBuffer*,
                             Vector<unsigned>* baselineHashes);
 
 void testByteByByteDecode(DecoderCreator createDecoder,
                           const char* file,
                           size_t expectedFrameCount,
@@ skipping 49 matching lines @@
 
 // Data is provided in chunks of length |increment| to the decoder. This value
 // can be increased to reduce processing time.
 void testProgressiveDecoding(DecoderCreator,
                              const char* file,
                              size_t increment = 1);
 void testProgressiveDecoding(DecoderCreator,
                              const char* dir,
                              const char* file,
                              size_t increment = 1);
+
+void testUpdateRequiredPreviousFrameAfterFirstDecode(DecoderCreator,
+                                                     const char* dir,
+                                                     const char* file);
+void testUpdateRequiredPreviousFrameAfterFirstDecode(DecoderCreator,
+                                                     const char* file);
+
+void testResumePartialDecodeAfterClearFrameBufferCache(DecoderCreator,
+                                                       const char* dir,
+                                                       const char* file);
+void testResumePartialDecodeAfterClearFrameBufferCache(DecoderCreator,
+                                                       const char* file);
+
+// Verifies that result of alpha blending is similar for AlphaPremultiplied and
+// AlphaNotPremultiplied cases.
+void testAlphaBlending(DecoderCreatorWithAlpha, const char*);
+
 }  // namespace blink