Return overlay resources to renderers in larger batches.

cc/output/gl_renderer.cc

Index: cc/output/gl_renderer.cc
diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index d3d4851682aee72852ed50da25067c24651b6f58..c1c5f70a0aa43d233a5c3e7a8931767b64971154 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -2660,21 +2660,26 @@ void GLRenderer::SwapBuffersComplete() {
       gl_->ScheduleCALayerInUseQueryCHROMIUM(textures.size(), textures.data());
     }
   } else if (swapping_overlay_resources_.size() > 1) {
+    resource_provider_->SetBatchReturnResources(true);

[Daniele Castagna, 2017/03/24 01:44:43]

Should we have something like ScopedBacthReturnResources instead?
Otherwise it seems like it could be easy to forget to set it back to false and
that would cause issues.

+
     // If a query is not needed to release the overlay buffers, we can assume
     // that once a swap buffer has completed we can remove the oldest buffers
     // from the queue.
     swapping_overlay_resources_.pop_front();
+    resource_provider_->SetBatchReturnResources(false);
   }
 }
 
 void GLRenderer::DidReceiveTextureInUseResponses(
     const gpu::TextureInUseResponses& responses) {
   DCHECK(settings_->release_overlay_resources_after_gpu_query);
+  resource_provider_->SetBatchReturnResources(true);
   for (const gpu::TextureInUseResponse& response : responses) {
     if (!response.in_use) {
       swapped_and_acked_overlay_resources_.erase(response.texture);
     }
   }
+  resource_provider_->SetBatchReturnResources(false);
   color_lut_cache_.Swap();
 }
 
@@ -3214,13 +3219,15 @@ void GLRenderer::ScheduleDCLayers() {
        current_frame()->dc_layer_overlay_list) {
     DCHECK(!dc_layer_overlay.rpdq);
 
-    ResourceId contents_resource_id = dc_layer_overlay.contents_resource_id;
     unsigned texture_id = 0;
-    if (contents_resource_id) {
-      pending_overlay_resources_.push_back(
-          base::MakeUnique<ResourceProvider::ScopedReadLockGL>(
-              resource_provider_, contents_resource_id));
-      texture_id = pending_overlay_resources_.back()->texture_id();
+    for (const auto& contents_resource_id : dc_layer_overlay.resources) {
+      if (contents_resource_id) {
+        pending_overlay_resources_.push_back(
+            base::MakeUnique<ResourceProvider::ScopedReadLockGL>(
+                resource_provider_, contents_resource_id));
+        if (!texture_id)
+          texture_id = pending_overlay_resources_.back()->texture_id();
+      }
     }
     GLfloat contents_rect[4] = {
         dc_layer_overlay.contents_rect.x(), dc_layer_overlay.contents_rect.y(),