cc: Async readback.

Provide a path to get a readback of a layer's subtree via an
asynchronous mechanism.

This path is used for all the cc pixel tests, to show that it
works. Also by some unit tests:

LayerTreeHostTestAsyncReadback.GLRenderer_RunSingleThread
LayerTreeHostTestAsyncReadback.GLRenderer_RunMultiThread
LayerTreeHostTestAsyncReadback.SoftwareRenderer_RunSingleThread
LayerTreeHostTestAsyncReadback.SoftwareRenderer_RunMultiThread
LayerTreeHostTestAsyncReadbackLayerDestroyed.RunSingleThread
LayerTreeHostTestAsyncReadbackLayerDestroyed.RunMultiThread

BUG=179896

Review URL: https://chromiumcodereview.appspot.com/14060015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@196747 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 13 insertions, 0 deletions

diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index 19b215b..4a0c7ba 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -1776,6 +1776,19 @@ void GLRenderer::EnsureScissorTestDisabled() {
   is_scissor_enabled_ = false;
 }
 
+void GLRenderer::CopyCurrentRenderPassToBitmap(DrawingFrame* frame,
+                                               SkBitmap* bitmap) {
+  gfx::Size render_pass_size = frame->current_render_pass->output_rect.size();
+  bitmap->setConfig(SkBitmap::kARGB_8888_Config,
+                    render_pass_size.width(),
+                    render_pass_size.height());
+  if (bitmap->allocPixels()) {
+    bitmap->lockPixels();
+    GetFramebufferPixels(bitmap->getPixels(), gfx::Rect(render_pass_size));
+    bitmap->unlockPixels();
+  }
+}
+
 void GLRenderer::ToGLMatrix(float* gl_matrix, const gfx::Transform& transform) {
   transform.matrix().asColMajorf(gl_matrix);
 }