cc: Lock resources directly in CALayerOverlay

cc/output/ca_layer_overlay.cc

Index: cc/output/ca_layer_overlay.cc
diff --git a/cc/output/ca_layer_overlay.cc b/cc/output/ca_layer_overlay.cc
index 3e53dd4d5d6918461330ff5d94375cd727a10374..b798fdb277b8952d372c335f8e7dcb931e8e7736 100644
--- a/cc/output/ca_layer_overlay.cc
+++ b/cc/output/ca_layer_overlay.cc
@@ -38,13 +38,23 @@ enum CALayerResult {
   CA_LAYER_FAILED_COUNT,
 };
 
+bool SetResource(ResourceProvider* resource_provider,

[erikchen, 2016/05/26 00:32:01]

I think the conditional should live outside the function. I don't really see the
point of this function. [It's doing too many things. SetResource should set a
resource, not conditionally set a resource.]

if (!resource_provider->IsOverlayCandidate(resource_id))	
       return CA_LAYER_FAILED_STREAM_VIDEO_NOT_CANDIDATE;

ca_layer_overlay->resource_lock = new
ResourceProvider::ScopedReadLockGpuMemoryBuffer(resource_provider, resource_id);

[ccameron, 2016/05/26 18:49:15]

But but ... it seems so wasteful to look the same structure up in the hash table
twice in a row!

The hope, though is that the next step will be to check
resource_lock->GetGpuMemoryBuffer, so the IsOverlayCandidate is to be short
lived. Made it not-lived.

+                 unsigned resource_id,
+                 CALayerOverlay* ca_layer_overlay) {
+  std::unique_ptr<ResourceProvider::ScopedReadLockGpuMemoryBuffer>
+      resource_lock(new ResourceProvider::ScopedReadLockGpuMemoryBuffer(
+          resource_provider, resource_id));
+  if (!resource_lock->IsOverlayCandidate())
+    return false;
+  ca_layer_overlay->resource_lock = std::move(resource_lock);
+  return true;
+}
+
 CALayerResult FromStreamVideoQuad(ResourceProvider* resource_provider,
                                   const StreamVideoDrawQuad* quad,
                                   CALayerOverlay* ca_layer_overlay) {
-  unsigned resource_id = quad->resource_id();
-  if (!resource_provider->IsOverlayCandidate(resource_id))
+  if (!SetResource(resource_provider, quad->resource_id(), ca_layer_overlay))
     return CA_LAYER_FAILED_STREAM_VIDEO_NOT_CANDIDATE;
-  ca_layer_overlay->contents_resource_id = resource_id;
   // TODO(ccameron): Support merging at least some basic transforms into the
   // layer transform.
   if (!quad->matrix.IsIdentity())
@@ -68,8 +78,7 @@ CALayerResult FromSolidColorDrawQuad(const SolidColorDrawQuad* quad,
 CALayerResult FromTextureQuad(ResourceProvider* resource_provider,
                               const TextureDrawQuad* quad,
                               CALayerOverlay* ca_layer_overlay) {
-  unsigned resource_id = quad->resource_id();
-  if (!resource_provider->IsOverlayCandidate(resource_id))
+  if (!SetResource(resource_provider, quad->resource_id(), ca_layer_overlay))
     return CA_LAYER_FAILED_TEXTURE_NOT_CANDIDATE;
   if (quad->y_flipped) {
     // The anchor point is at the bottom-left corner of the CALayer. The
@@ -80,7 +89,6 @@ CALayerResult FromTextureQuad(ResourceProvider* resource_provider,
         0, ca_layer_overlay->bounds_rect.height(), 0);
     ca_layer_overlay->transform.preScale(1, -1, 1);
   }
-  ca_layer_overlay->contents_resource_id = resource_id;
   ca_layer_overlay->contents_rect =
       BoundingRect(quad->uv_top_left, quad->uv_bottom_right);
   ca_layer_overlay->background_color = quad->background_color;
@@ -96,10 +104,8 @@ CALayerResult FromTextureQuad(ResourceProvider* resource_provider,
 CALayerResult FromTileQuad(ResourceProvider* resource_provider,
                            const TileDrawQuad* quad,
                            CALayerOverlay* ca_layer_overlay) {
-  unsigned resource_id = quad->resource_id();
-  if (!resource_provider->IsOverlayCandidate(resource_id))
+  if (!SetResource(resource_provider, quad->resource_id(), ca_layer_overlay))
     return CA_LAYER_FAILED_TILE_NOT_CANDIDATE;
-  ca_layer_overlay->contents_resource_id = resource_id;
   ca_layer_overlay->contents_rect = quad->tex_coord_rect;
   ca_layer_overlay->contents_rect.Scale(1.f / quad->texture_size.width(),
                                         1.f / quad->texture_size.height());
@@ -178,7 +184,7 @@ CALayerResult FromDrawQuad(ResourceProvider* resource_provider,
 
 CALayerOverlay::CALayerOverlay() : filter(GL_LINEAR) {}
 
-CALayerOverlay::CALayerOverlay(const CALayerOverlay& other) = default;
+CALayerOverlay::CALayerOverlay(CALayerOverlay&& other) = default;
 
 CALayerOverlay::~CALayerOverlay() {}
 
@@ -217,7 +223,7 @@ bool ProcessForCALayerOverlays(ResourceProvider* resource_provider,
       }
     }
 
-    ca_layer_overlays->push_back(ca_layer);
+    ca_layer_overlays->push_back(std::move(ca_layer));
   }
 
   UMA_HISTOGRAM_ENUMERATION("Compositing.Renderer.CALayerResult", result,