Cheaper thread-safe atomic initialization of static references.

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 34 matching lines @@
 {
     return SkImageInfo::Make(100, 100, kBGRA_8888_SkColorType, kOpaque_SkAlphaType);
 }
 
 } // namespace
 
 class ImageFrameGeneratorTest : public ::testing::Test, public MockImageDecoderClient {
 public:
     virtual void SetUp() override
     {
-        ImageDecodingStore::instance()->setCacheLimitInBytes(1024 * 1024);
+        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();
+        ImageDecodingStore::instance().clear();
     }
 
     virtual void decoderBeingDestroyed() override
     {
         ++m_decodersDestroyed;
     }
 
     virtual void frameBufferRequested() override
     {
         ++m_frameBufferRequestCount;
@@ skipping 110 matching lines @@
 TEST_F(ImageFrameGeneratorTest, frameHasAlpha)
 {
     setFrameStatus(ImageFrame::FramePartial);
 
     char buffer[100 * 100 * 4];
     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));
+    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);
+    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);
@@ skipping 12 matching lines @@
 
     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