cc: Made image comparison for pixel tests error tolerant.

ui/compositor/layer_unittest.cc

 // Copyright (c) 2012 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 "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
 #include "cc/layers/layer.h"
 #include "cc/output/delegated_frame_data.h"
 #include "cc/test/pixel_test_utils.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/compositor/compositor_observer.h"
 #include "ui/compositor/compositor_setup.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_animation_sequence.h"
 #include "ui/compositor/layer_animator.h"
 #include "ui/compositor/test/test_compositor_host.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/codec/png_codec.h"
 #include "ui/gfx/gfx_paths.h"
 #include "ui/gfx/skia_util.h"
 
-using cc::IsSameAsPNGFile;
+using cc::MatchesPNGFile;
 
 namespace ui {
 
 namespace {
 
 // Returns a comma-separated list of the names of |layer|'s children in
 // bottom-to-top stacking order.
 std::string GetLayerChildrenNames(const Layer& layer) {
   std::string names;
   for (std::vector<Layer*>::const_iterator it = layer.children().begin();
@@ skipping 873 matching lines @@
       test_data_directory().AppendASCII("ModifyHierarchy2.png");
   SkBitmap bitmap;
 
   l0->Add(l11.get());
   l11->Add(l21.get());
   l0->Add(l12.get());
   DrawTree(l0.get());
   ASSERT_TRUE(ReadPixels(&bitmap));
   ASSERT_FALSE(bitmap.empty());
   // WritePNGFile(bitmap, ref_img1);
-  EXPECT_TRUE(IsSameAsPNGFile(bitmap, ref_img1, true));
+  EXPECT_TRUE(MatchesPNGFile(bitmap, ref_img1, cc::ExactPixelComparator(true)));
 
   l0->StackAtTop(l11.get());
   DrawTree(l0.get());
   ASSERT_TRUE(ReadPixels(&bitmap));
   ASSERT_FALSE(bitmap.empty());
   // WritePNGFile(bitmap, ref_img2);
-  EXPECT_TRUE(IsSameAsPNGFile(bitmap, ref_img2, true));
+  EXPECT_TRUE(MatchesPNGFile(bitmap, ref_img2, cc::ExactPixelComparator(true)));
 
   // l11 is already at the front, should have no effect.
   l0->StackAtTop(l11.get());
   DrawTree(l0.get());
   ASSERT_TRUE(ReadPixels(&bitmap));
   ASSERT_FALSE(bitmap.empty());
-  EXPECT_TRUE(IsSameAsPNGFile(bitmap, ref_img2, true));
+  EXPECT_TRUE(MatchesPNGFile(bitmap, ref_img2, cc::ExactPixelComparator(true)));
 
   // l11 is already at the front, should have no effect.
   l0->StackAbove(l11.get(), l12.get());
   DrawTree(l0.get());
   ASSERT_TRUE(ReadPixels(&bitmap));
   ASSERT_FALSE(bitmap.empty());
-  EXPECT_TRUE(IsSameAsPNGFile(bitmap, ref_img2, true));
+  EXPECT_TRUE(MatchesPNGFile(bitmap, ref_img2, cc::ExactPixelComparator(true)));
 
   // should restore to original configuration
   l0->StackAbove(l12.get(), l11.get());
   DrawTree(l0.get());
   ASSERT_TRUE(ReadPixels(&bitmap));
   ASSERT_FALSE(bitmap.empty());
-  EXPECT_TRUE(IsSameAsPNGFile(bitmap, ref_img1, true));
+  EXPECT_TRUE(MatchesPNGFile(bitmap, ref_img1, cc::ExactPixelComparator(true)));
 }
 
 // Opacity is rendered correctly.
 // Checks that modifying the hierarchy correctly affects final composite.
 TEST_F(LayerWithRealCompositorTest, MAYBE_Opacity) {
   GetCompositor()->SetScaleAndSize(1.0f, gfx::Size(50, 50));
 
   // l0
   //  +-l11
   scoped_ptr<Layer> l0(CreateColorLayer(SK_ColorRED,
                                         gfx::Rect(0, 0, 50, 50)));
   scoped_ptr<Layer> l11(CreateColorLayer(SK_ColorGREEN,
                                          gfx::Rect(0, 0, 25, 25)));
 
   base::FilePath ref_img = test_data_directory().AppendASCII("Opacity.png");
 
   l11->SetOpacity(0.75);
   l0->Add(l11.get());
   DrawTree(l0.get());
   SkBitmap bitmap;
   ASSERT_TRUE(ReadPixels(&bitmap));
   ASSERT_FALSE(bitmap.empty());
   // WritePNGFile(bitmap, ref_img);
-  EXPECT_TRUE(IsSameAsPNGFile(bitmap, ref_img, true));
+  EXPECT_TRUE(MatchesPNGFile(bitmap, ref_img, cc::ExactPixelComparator(true)));
 }
 
 namespace {
 
 class SchedulePaintLayerDelegate : public LayerDelegate {
  public:
   SchedulePaintLayerDelegate() : paint_count_(0), layer_(NULL) {}
 
   virtual ~SchedulePaintLayerDelegate() {}
 
@@ skipping 391 matching lines @@
   l1->SetOpacity(0.5f);
 
   // Change l1's cc::Layer.
   l1->SwitchCCLayerForTest();
 
   // Ensure that the opacity animation completed.
   EXPECT_FLOAT_EQ(l1->opacity(), 0.5f);
 }
 
 }  // namespace ui