cc: Fix readback from non-root layers.

cc/trees/layer_tree_host_pixeltest_readback.cc

Index: cc/trees/layer_tree_host_pixeltest_readback.cc
diff --git a/cc/trees/layer_tree_host_pixeltest_readback.cc b/cc/trees/layer_tree_host_pixeltest_readback.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f6a6ccbbb701b9143d9f9b9a7836e318a10734b5
--- /dev/null
+++ b/cc/trees/layer_tree_host_pixeltest_readback.cc
@@ -0,0 +1,94 @@
+// Copyright 2013 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 "build/build_config.h"
+#include "cc/test/layer_tree_pixel_test.h"
+
+#if !defined(OS_ANDROID)
+
+namespace cc {
+namespace {
+
+class LayerTreeHostReadbackPixelTest : public LayerTreePixelTest {};
+
+TEST_F(LayerTreeHostReadbackPixelTest, ReadbackRootLayer) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(200, 200), SK_ColorGREEN);
+  background->AddChild(green);
+
+  RunPixelTest(background,
+               base::FilePath(FILE_PATH_LITERAL(
+                   "green.png")));
+}
+
+TEST_F(LayerTreeHostReadbackPixelTest, ReadbackRootLayerWithChild) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(200, 200), SK_ColorGREEN);
+  background->AddChild(green);
+
+  scoped_refptr<SolidColorLayer> blue = CreateSolidColorLayer(
+      gfx::Rect(150, 150, 50, 50), SK_ColorBLUE);
+  green->AddChild(blue);
+
+  RunPixelTest(background,
+               base::FilePath(FILE_PATH_LITERAL(
+                   "green_with_blue_corner.png")));
+}
+
+TEST_F(LayerTreeHostReadbackPixelTest, ReadbackNonRootLayer) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(200, 200), SK_ColorGREEN);
+  background->AddChild(green);
+
+  RunPixelTestWithReadbackTarget(background,
+                                 green.get(),
+                                 base::FilePath(FILE_PATH_LITERAL(
+                                     "green.png")));
+}
+
+TEST_F(LayerTreeHostReadbackPixelTest, ReadbackSmallNonRootLayer) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(100, 100, 100, 100), SK_ColorGREEN);
+  background->AddChild(green);
+
+  RunPixelTestWithReadbackTarget(background,
+                                 green.get(),
+                                 base::FilePath(FILE_PATH_LITERAL(
+                                     "green_small.png")));
+}
+
+TEST_F(LayerTreeHostReadbackPixelTest, ReadbackSmallNonRootLayerWithChild) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(100, 100, 100, 100), SK_ColorGREEN);
+  background->AddChild(green);
+
+  scoped_refptr<SolidColorLayer> blue = CreateSolidColorLayer(
+      gfx::Rect(50, 50, 50, 50), SK_ColorBLUE);
+  green->AddChild(blue);
+
+  RunPixelTestWithReadbackTarget(background,
+                                 green.get(),
+                                 base::FilePath(FILE_PATH_LITERAL(
+                                     "green_small_with_blue_corner.png")));
+}
+
+}  // namespace
+}  // namespace cc
+
+#endif  // OS_ANDROID