cc_blink: Remove ownership of cc::Layer from WebLayer.

This is a precursor to deleting WebLayer. It makes WebLayer hold a raw
cc::Layer* pointer, forcing each owner of a WebLayer to also own a
scoped_refptr<cc::Layer>. Then we can remove the unique_ptr<WebLayer>s
in the future.

[email protected]

Bug: 838693
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: If0f3f68a4fb741acea33b81a1b468a6a3d0a93ad
Reviewed-on: https://chromium-review.googlesource.com/1054589
Reviewed-by: Antoine Labour <[email protected]>
Reviewed-by: Philip Rogers <[email protected]>
Reviewed-by: Xiaohan Wang <[email protected]>
Commit-Queue: danakj <[email protected]>
Cr-Commit-Position: refs/heads/master@{#557948}
diff --git a/content/renderer/child_frame_compositing_helper.cc b/content/renderer/child_frame_compositing_helper.cc
index 78bccec..ee3bf0a 100644
--- a/content/renderer/child_frame_compositing_helper.cc
+++ b/content/renderer/child_frame_compositing_helper.cc
@@ -67,9 +67,8 @@
   }
 
   bool prevent_contents_opaque_changes = false;
-  child_frame_compositor_->SetLayer(
-      std::make_unique<cc_blink::WebLayerImpl>(crashed_layer),
-      prevent_contents_opaque_changes);
+  child_frame_compositor_->SetLayer(std::move(crashed_layer),
+                                    prevent_contents_opaque_changes);
 }
 
 void ChildFrameCompositingHelper::SetPrimarySurfaceId(
@@ -89,18 +88,15 @@
   surface_layer_->SetPrimarySurfaceId(surface_id, deadline);
   surface_layer_->SetFallbackSurfaceId(fallback_surface_id_);
 
-  auto layer_owned = std::make_unique<cc_blink::WebLayerImpl>(surface_layer_);
-  auto* layer = layer_owned.get();
-
   // TODO(lfg): Investigate if it's possible to propagate the information
   // about the child surface's opacity. https://crbug.com/629851.
   bool prevent_contents_opaque_changes = true;
-  child_frame_compositor_->SetLayer(std::move(layer_owned),
+  child_frame_compositor_->SetLayer(surface_layer_,
                                     prevent_contents_opaque_changes);
 
   UpdateVisibility(true);
 
-  layer->SetBounds(frame_size_in_dip);
+  surface_layer_->SetBounds(frame_size_in_dip);
 }
 
 void ChildFrameCompositingHelper::SetFallbackSurfaceId(