Fixing Canvas2DLayerBridge to handle lost graphics contexts

Source/WebKit/chromium/tests/Canvas2DLayerBridgeTest.cpp

 /*
  * Copyright (C) 2011 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
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 40 matching lines @@
     MOCK_METHOD1(deleteTexture, void(unsigned));
 
     virtual GrGLInterface* onCreateGrGLInterface() OVERRIDE { return 0; }
 };
 
 class MockWebTextureUpdater : public WebTextureUpdater {
 public:
     MOCK_METHOD3(appendCopy, void(unsigned, unsigned, WebSize));
 };
 
+class FakeCanvas2DLayerBridge : public Canvas2DLayerBridge {
+public:
+    static PassOwnPtr<Canvas2DLayerBridge> create(PassRefPtr<GraphicsContext3D> context, SkDeferredCanvas* canvas, OpacityMode opacityMode, ThreadMode threadMode)
+    {
+        return adoptPtr(new FakeCanvas2DLayerBridge(context, canvas, opacityMode, threadMode));
+    }
+
+    virtual bool isValid() OVERRIDE

[Stephen White, 2013/05/28 18:05:43]

Now that we have a virtual isValid(), maybe we could use it for testing for the
correct behaviour in the lost-context case.

+    {
+        return true;
+    }
+protected:
+    FakeCanvas2DLayerBridge(PassRefPtr<GraphicsContext3D> context, SkDeferredCanvas* canvas, OpacityMode opacityMode, ThreadMode threadMode) :
+        Canvas2DLayerBridge(context, canvas)
+    {
+        init(opacityMode, threadMode);
+    }
+};
+
 } // namespace
 
 class Canvas2DLayerBridgeTest : public Test {
 protected:
     void fullLifecycleTest(Canvas2DLayerBridge::ThreadMode threadMode)
     {
         RefPtr<GraphicsContext3D> mainContext = GraphicsContext3D::createGraphicsContextFromWebContext(adoptPtr(new MockCanvasContext));
 
         MockCanvasContext& mainMock = *static_cast<MockCanvasContext*>(mainContext->webContext());
 
         MockWebTextureUpdater updater;
 
         SkDevice device(SkBitmap::kARGB_8888_Config, 300, 150);
         SkDeferredCanvas canvas(&device);
 
         ::testing::Mock::VerifyAndClearExpectations(&mainMock);
 
-        OwnPtr<Canvas2DLayerBridge> bridge = Canvas2DLayerBridge::create(mainContext.release(), &canvas, Canvas2DLayerBridge::NonOpaque, threadMode);
+        OwnPtr<Canvas2DLayerBridge> bridge = FakeCanvas2DLayerBridge::create(mainContext.release(), &canvas, Canvas2DLayerBridge::NonOpaque, threadMode);
 
         ::testing::Mock::VerifyAndClearExpectations(&mainMock);
 
         EXPECT_CALL(mainMock, flush());
         unsigned textureId = bridge->backBufferTexture();
         EXPECT_TRUE(textureId == 0);
 
         ::testing::Mock::VerifyAndClearExpectations(&mainMock);
 
         bridge.clear();
 
         ::testing::Mock::VerifyAndClearExpectations(&mainMock);
         ::testing::Mock::VerifyAndClearExpectations(&updater);
     }
 };
 
 namespace {
 
 TEST_F(Canvas2DLayerBridgeTest, testFullLifecycleSingleThreaded)
 {
     fullLifecycleTest(Canvas2DLayerBridge::SingleThread);
 }
 
 TEST_F(Canvas2DLayerBridgeTest, testFullLifecycleThreaded)
 {
     fullLifecycleTest(Canvas2DLayerBridge::Threaded);
 }
 
 } // namespace