GIF decoding: Add a unit test for repetition count

third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoderTest.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
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@@ skipping 482 matching lines @@
         if (decoder->isSizeAvailable() && !frameSize.width() && !frameSize.height()) {
             frameSize = decoder->decodedSize();
             continue;
         }
 
         ASSERT_EQ(frameSize.width(), decoder->decodedSize().width());
         ASSERT_EQ(frameSize.height(), decoder->decodedSize().height());
     }
 }
 
+TEST(GIFImageDecoderTest, verifyRepetitionCount)
+{
+    const int expectedRepetitionCount = 2;
+    OwnPtr<ImageDecoder> decoder = createDecoder();
+    RefPtr<SharedBuffer> data = readFile(layoutTestResourcesDir, "full2loop.gif");
+    ASSERT_TRUE(data.get());
+    decoder->setData(data.get(), true);
+    EXPECT_EQ(cAnimationLoopOnce, decoder->repetitionCount()); // Default value before decode.
+
+    ImageFrame* frame = decoder->frameBufferAtIndex(0);
+    EXPECT_EQ(ImageFrame::FrameComplete, frame->getStatus());
+    frame = decoder->frameBufferAtIndex(1);
+    EXPECT_EQ(ImageFrame::FrameComplete, frame->getStatus());
+

[Noel Gordon, 2016/03/11 00:39:50]

Are there 2, or 3, frames in the test GIF image?  Seems to me that there were 3
frames when I looked at test image in the Mac OSX image viewer tool.  Is that
tool wrong?

[urvang, 2016/03/11 01:13:49]

Yes, there are 3 frames, with repetition count of 2.

We are just testing the repetition count here.

+    EXPECT_EQ(expectedRepetitionCount, decoder->repetitionCount()); // Expected value after decode.
+}
+
 } // namespace blink