Remove multi-frame image decoder when the image is completely decoded

Source/platform/graphics/ImageFrameGeneratorTest.cpp

 /*
  * Copyright (C) 2012 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 met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 41 matching lines @@
 public:
     virtual void SetUp() override
     {
         ImageDecodingStore::instance()->setCacheLimitInBytes(1024 * 1024);
         m_data = SharedBuffer::create();
         m_generator = ImageFrameGenerator::create(fullSize(), m_data, false);
         useMockImageDecoderFactory();
         m_decodersDestroyed = 0;
         m_frameBufferRequestCount = 0;
         m_status = ImageFrame::FrameEmpty;
+        m_frameCount = 1;
     }
 
     virtual void TearDown() override
     {
         ImageDecodingStore::instance()->clear();
     }
 
     virtual void decoderBeingDestroyed() override
     {
         ++m_decodersDestroyed;
     }
 
     virtual void frameBufferRequested() override
     {
         ++m_frameBufferRequestCount;
     }
 
     virtual ImageFrame::Status status() override
     {
         ImageFrame::Status currentStatus = m_status;
         m_status = m_nextFrameStatus;
         return currentStatus;
     }
 
-    virtual size_t frameCount() override { return 1; }
-    virtual int repetitionCount() const override { return cAnimationNone; }
+    virtual size_t frameCount() override { return m_frameCount; }
+    virtual int repetitionCount() const override { return m_frameCount == 1 ? cAnimationNone:cAnimationLoopOnce; }
     virtual float frameDuration() const override { return 0; }
 
 protected:
     void useMockImageDecoderFactory()
     {
         m_generator->setImageDecoderFactory(MockImageDecoderFactory::create(this, fullSize()));
     }
 
     void addNewData()
     {
         m_data->append("g", 1);
         m_generator->setData(m_data, false);
     }
 
     void setFrameStatus(ImageFrame::Status status)  { m_status = m_nextFrameStatus = status; }
     void setNextFrameStatus(ImageFrame::Status status)  { m_nextFrameStatus = status; }
+    void setFrameCount(size_t count)
+    {
+        m_frameCount = count;
+        if (count > 1) {
+            m_generator.clear();
+            m_generator = ImageFrameGenerator::create(fullSize(), m_data, true, true);
+            useMockImageDecoderFactory();
+        }
+    }
 
     RefPtr<SharedBuffer> m_data;
     RefPtr<ImageFrameGenerator> m_generator;
     int m_decodersDestroyed;
     int m_frameBufferRequestCount;
     ImageFrame::Status m_status;
     ImageFrame::Status m_nextFrameStatus;
+    size_t m_frameCount;
 };
 
 TEST_F(ImageFrameGeneratorTest, incompleteDecode)
 {
     setFrameStatus(ImageFrame::FramePartial);
 
     char buffer[100 * 100 * 4];
     m_generator->decodeAndScale(imageInfo(), 0, buffer, 100 * 4);
     EXPECT_EQ(1, m_frameBufferRequestCount);
 
@@ skipping 51 matching lines @@
     // Decoder created again.
     m_generator->decodeAndScale(imageInfo(), 0, buffer, 100 * 4);
     EXPECT_EQ(3, m_frameBufferRequestCount);
 }
 
 TEST_F(ImageFrameGeneratorTest, frameHasAlpha)
 {
     setFrameStatus(ImageFrame::FramePartial);
 
     char buffer[100 * 100 * 4];
-    m_generator->decodeAndScale(imageInfo(), 1, buffer, 100 * 4);
-    EXPECT_TRUE(m_generator->hasAlpha(1));
+    m_generator->decodeAndScale(imageInfo(), 0, buffer, 100 * 4);
+    EXPECT_TRUE(m_generator->hasAlpha(0));
     EXPECT_EQ(1, m_frameBufferRequestCount);
 
     ImageDecoder* tempDecoder = 0;
     EXPECT_TRUE(ImageDecodingStore::instance()->lockDecoder(m_generator.get(), fullSize(), &tempDecoder));
     ASSERT_TRUE(tempDecoder);
     static_cast<MockImageDecoder*>(tempDecoder)->setFrameHasAlpha(false);
     ImageDecodingStore::instance()->unlockDecoder(m_generator.get(), tempDecoder);
 
     setFrameStatus(ImageFrame::FrameComplete);
+    m_generator->decodeAndScale(imageInfo(), 0, buffer, 100 * 4);
+    EXPECT_EQ(2, m_frameBufferRequestCount);
+    EXPECT_FALSE(m_generator->hasAlpha(0));
+}
+
+TEST_F(ImageFrameGeneratorTest, removeMultiFrameDecoder)
+{
+    setFrameCount(3);
+    setFrameStatus(ImageFrame::FrameComplete);
+
+    char buffer[100 * 100 * 4];
+    m_generator->decodeAndScale(imageInfo(), 0, buffer, 100 * 4);
+    EXPECT_EQ(1, m_frameBufferRequestCount);
+    EXPECT_EQ(0, m_decodersDestroyed);
+
+    setFrameStatus(ImageFrame::FrameComplete);
+
     m_generator->decodeAndScale(imageInfo(), 1, buffer, 100 * 4);
     EXPECT_EQ(2, m_frameBufferRequestCount);
-    EXPECT_FALSE(m_generator->hasAlpha(1));
+    EXPECT_EQ(0, m_decodersDestroyed);
+
+    setFrameStatus(ImageFrame::FrameComplete);
+
+    // Multi frame decoder should be removed.
+    m_generator->decodeAndScale(imageInfo(), 2, buffer, 100 * 4);
+    EXPECT_EQ(3, m_frameBufferRequestCount);
+    EXPECT_EQ(1, m_decodersDestroyed);
 }
 
 } // namespace blink