cc: Detect miss-behaving fence extensions when using 1-copy rasterizer.

This adds a wait_if_needed parameter to
ResourcePool::CheckBusyResources. CheckBusyResources will use existing
ResourceProvider API to wait for any read locks to complete if needed
by a resource prior to checking if it's still busy when this parameter
is true.

1-copy rasterizer will use this functionality after too many failed
attempts to check if copy operations have completed. This provides a
reliable method to detect drivers with miss-behaving fence extensions.

BUG=406404

Review URL: https://codereview.chromium.org/683263004

Cr-Commit-Position: refs/heads/master@{#301926}

1 files changed, 4 insertions, 1 deletions

diff --git a/cc/resources/resource_pool.cc b/cc/resources/resource_pool.cc
index 31b9b27..45f36e2 100644
--- a/cc/resources/resource_pool.cc
+++ b/cc/resources/resource_pool.cc
@@ -105,12 +105,15 @@ bool ResourcePool::ResourceUsageTooHigh() {
   return false;
 }
 
-void ResourcePool::CheckBusyResources() {
+void ResourcePool::CheckBusyResources(bool wait_if_needed) {
   ResourceList::iterator it = busy_resources_.begin();
 
   while (it != busy_resources_.end()) {
     ScopedResource* resource = *it;
 
+    if (wait_if_needed)
+      resource_provider_->WaitReadLockIfNeeded(resource->id());
+
     if (resource_provider_->CanLockForWrite(resource->id())) {
       DidFinishUsingResource(resource);
       it = busy_resources_.erase(it);