Fix copy_rect calculation in CopyCurrentRendererPassToBitmap().

The calculation was second-guessing the copy request's subrect by force-translating its origin.  This manifested as bug 280724, where the compositing layer for Flash fullscreen was being read back with erroneous -64 by -64 translation.

Digging deeper, the RenderPass was drawing to output_rect=(-64, -64, screen_width+64, screen_height+64).  The client was requesting area=(0, 0, screen_width, screen_height), and this is actually the correct region within the output_rect for the fullscreen content.

Testing:

1. Ran cc_unittests --gtest_filter='*Readback*'
2. Installed Chromecast extension, and mirrored both normal tab content and fullscreen Flash content to Chromecast device.

BUG=280724

Review URL: https://chromiumcodereview.appspot.com/23967012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@223722 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 154 insertions, 14 deletions

diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index 074d603..89fe9de 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -1967,11 +1967,8 @@ void GLRenderer::CopyCurrentRenderPassToBitmap(
     DrawingFrame* frame,
     scoped_ptr<CopyOutputRequest> request) {
   gfx::Rect copy_rect = frame->current_render_pass->output_rect;
-  if (request->has_area()) {
-    // Intersect with the request's area, positioned with its origin at the
-    // origin of the full copy_rect.
-    copy_rect.Intersect(request->area() - copy_rect.OffsetFromOrigin());
-  }
+  if (request->has_area())
+    copy_rect.Intersect(request->area());
   GetFramebufferPixelsAsync(copy_rect, request.Pass());
 }
 
@@ -2188,10 +2185,6 @@ void GLRenderer::GetFramebufferPixelsAsync(
   if (rect.IsEmpty())
     return;
 
-  DCHECK(gfx::Rect(current_surface_size_).Contains(rect)) <<
-      "current_surface_size_: " << current_surface_size_.ToString() <<
-      " rect: " << rect.ToString();
-
   gfx::Rect window_rect = MoveFromDrawToWindowSpace(rect);
 
   if (!request->force_bitmap_result()) {
diff --git a/cc/output/software_renderer.cc b/cc/output/software_renderer.cc
index 241968e..394d79a 100644
--- a/cc/output/software_renderer.cc
+++ b/cc/output/software_renderer.cc
@@ -492,11 +492,8 @@ void SoftwareRenderer::CopyCurrentRenderPassToBitmap(
     DrawingFrame* frame,
     scoped_ptr<CopyOutputRequest> request) {
   gfx::Rect copy_rect = frame->current_render_pass->output_rect;
-  if (request->has_area()) {
-    // Intersect with the request's area, positioned with its origin at the
-    // origin of the full copy_rect.
-    copy_rect.Intersect(request->area() - copy_rect.OffsetFromOrigin());
-  }
+  if (request->has_area())
+    copy_rect.Intersect(request->area());
   gfx::Rect window_copy_rect = MoveFromDrawToWindowSpace(copy_rect);
 
   scoped_ptr<SkBitmap> bitmap(new SkBitmap);
diff --git a/cc/trees/layer_tree_host_pixeltest_readback.cc b/cc/trees/layer_tree_host_pixeltest_readback.cc
index 28b80b9..d8e2861 100644
--- a/cc/trees/layer_tree_host_pixeltest_readback.cc
+++ b/cc/trees/layer_tree_host_pixeltest_readback.cc
@@ -335,6 +335,156 @@ TEST_F(LayerTreeHostReadbackPixelTest, ReadbackSmallNonRootLayerWithChild_GL) {
                                      "green_small_with_blue_corner.png")));
 }
 
+TEST_F(LayerTreeHostReadbackPixelTest,
+       ReadbackSubtreeSurroundsTargetLayer_Software) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(0, 0, 200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> target = CreateSolidColorLayer(
+      gfx::Rect(100, 100, 100, 100), SK_ColorRED);
+  background->AddChild(target);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(-100, -100, 300, 300), SK_ColorGREEN);
+  target->AddChild(green);
+
+  scoped_refptr<SolidColorLayer> blue = CreateSolidColorLayer(
+      gfx::Rect(50, 50, 50, 50), SK_ColorBLUE);
+  target->AddChild(blue);
+
+  copy_subrect_ = gfx::Rect(0, 0, 100, 100);
+  RunPixelTestWithReadbackTarget(SOFTWARE_WITH_DEFAULT,
+                                 background,
+                                 target.get(),
+                                 base::FilePath(FILE_PATH_LITERAL(
+                                     "green_small_with_blue_corner.png")));
+}
+
+TEST_F(LayerTreeHostReadbackPixelTest,
+       ReadbackSubtreeSurroundsLayer_GL_Bitmap) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(0, 0, 200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> target = CreateSolidColorLayer(
+      gfx::Rect(100, 100, 100, 100), SK_ColorRED);
+  background->AddChild(target);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(-100, -100, 300, 300), SK_ColorGREEN);
+  target->AddChild(green);
+
+  scoped_refptr<SolidColorLayer> blue = CreateSolidColorLayer(
+      gfx::Rect(50, 50, 50, 50), SK_ColorBLUE);
+  target->AddChild(blue);
+
+  copy_subrect_ = gfx::Rect(0, 0, 100, 100);
+  RunPixelTestWithReadbackTarget(GL_WITH_BITMAP,
+                                 background,
+                                 target.get(),
+                                 base::FilePath(FILE_PATH_LITERAL(
+                                     "green_small_with_blue_corner.png")));
+}
+
+TEST_F(LayerTreeHostReadbackPixelTest,
+       ReadbackSubtreeSurroundsTargetLayer_GL) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(0, 0, 200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> target = CreateSolidColorLayer(
+      gfx::Rect(100, 100, 100, 100), SK_ColorRED);
+  background->AddChild(target);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(-100, -100, 300, 300), SK_ColorGREEN);
+  target->AddChild(green);
+
+  scoped_refptr<SolidColorLayer> blue = CreateSolidColorLayer(
+      gfx::Rect(50, 50, 50, 50), SK_ColorBLUE);
+  target->AddChild(blue);
+
+  copy_subrect_ = gfx::Rect(0, 0, 100, 100);
+  RunPixelTestWithReadbackTarget(GL_WITH_DEFAULT,
+                                 background,
+                                 target.get(),
+                                 base::FilePath(FILE_PATH_LITERAL(
+                                     "green_small_with_blue_corner.png")));
+}
+
+TEST_F(LayerTreeHostReadbackPixelTest,
+       ReadbackSubtreeExtendsBeyondTargetLayer_Software) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(0, 0, 200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> target = CreateSolidColorLayer(
+      gfx::Rect(50, 50, 150, 150), SK_ColorRED);
+  background->AddChild(target);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(50, 50, 200, 200), SK_ColorGREEN);
+  target->AddChild(green);
+
+  scoped_refptr<SolidColorLayer> blue = CreateSolidColorLayer(
+      gfx::Rect(100, 100, 50, 50), SK_ColorBLUE);
+  target->AddChild(blue);
+
+  copy_subrect_ = gfx::Rect(50, 50, 100, 100);
+  RunPixelTestWithReadbackTarget(SOFTWARE_WITH_DEFAULT,
+                                 background,
+                                 target.get(),
+                                 base::FilePath(FILE_PATH_LITERAL(
+                                     "green_small_with_blue_corner.png")));
+}
+
+TEST_F(LayerTreeHostReadbackPixelTest,
+       ReadbackSubtreeExtendsBeyondTargetLayer_GL_Bitmap) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(0, 0, 200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> target = CreateSolidColorLayer(
+      gfx::Rect(50, 50, 150, 150), SK_ColorRED);
+  background->AddChild(target);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(50, 50, 200, 200), SK_ColorGREEN);
+  target->AddChild(green);
+
+  scoped_refptr<SolidColorLayer> blue = CreateSolidColorLayer(
+      gfx::Rect(100, 100, 50, 50), SK_ColorBLUE);
+  target->AddChild(blue);
+
+  copy_subrect_ = gfx::Rect(50, 50, 100, 100);
+  RunPixelTestWithReadbackTarget(GL_WITH_BITMAP,
+                                 background,
+                                 target.get(),
+                                 base::FilePath(FILE_PATH_LITERAL(
+                                     "green_small_with_blue_corner.png")));
+}
+
+TEST_F(LayerTreeHostReadbackPixelTest,
+       ReadbackSubtreeExtendsBeyondTargetLayer_GL) {
+  scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
+      gfx::Rect(0, 0, 200, 200), SK_ColorWHITE);
+
+  scoped_refptr<SolidColorLayer> target = CreateSolidColorLayer(
+      gfx::Rect(50, 50, 150, 150), SK_ColorRED);
+  background->AddChild(target);
+
+  scoped_refptr<SolidColorLayer> green = CreateSolidColorLayer(
+      gfx::Rect(50, 50, 200, 200), SK_ColorGREEN);
+  target->AddChild(green);
+
+  scoped_refptr<SolidColorLayer> blue = CreateSolidColorLayer(
+      gfx::Rect(100, 100, 50, 50), SK_ColorBLUE);
+  target->AddChild(blue);
+
+  copy_subrect_ = gfx::Rect(50, 50, 100, 100);
+  RunPixelTestWithReadbackTarget(GL_WITH_DEFAULT,
+                                 background,
+                                 target.get(),
+                                 base::FilePath(FILE_PATH_LITERAL(
+                                     "green_small_with_blue_corner.png")));
+}
+
 TEST_F(LayerTreeHostReadbackPixelTest, ReadbackSubrect_Software) {
   scoped_refptr<SolidColorLayer> background = CreateSolidColorLayer(
       gfx::Rect(200, 200), SK_ColorWHITE);