cc: Add CopyResource function to ResourceProvider API.

This provides an efficient mechanism for copying a resource.
Source and destination resources must have matching dimensions
and format. Source resource can be backed by an image but
destination cannot. CopyResource creates the appropritate read
lock fence to prevent unsafe access to source image before
the operation has completed.

Also moves the toggle of frame based read lock fences out of
the ResourcePool to not conflict with the read lock fences needed
for CopyResource.

BUG=269808

Review URL: https://codereview.chromium.org/234403005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@263761 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 0 insertions, 6 deletions

diff --git a/cc/resources/resource_pool.cc b/cc/resources/resource_pool.cc
index 7170a39..31b9b27 100644
--- a/cc/resources/resource_pool.cc
+++ b/cc/resources/resource_pool.cc
@@ -51,16 +51,10 @@ scoped_ptr<ScopedResource> ResourcePool::AcquireResource(
     return make_scoped_ptr(resource);
   }
 
-  // Create new resource.
   scoped_ptr<ScopedResource> resource =
       ScopedResource::Create(resource_provider_);
   resource->AllocateManaged(size, target_, format_);
 
-  // Extend all read locks on all resources until the resource is
-  // finished being used, such that we know when resources are
-  // truly safe to recycle.
-  resource_provider_->EnableReadLockFences(resource->id(), true);
-
   memory_usage_bytes_ += resource->bytes();
   ++resource_count_;
   return resource.Pass();