ui: Add ref-counting to GLFence class.

gpu/command_buffer/service/mailbox_manager_sync.cc

Index: gpu/command_buffer/service/mailbox_manager_sync.cc
diff --git a/gpu/command_buffer/service/mailbox_manager_sync.cc b/gpu/command_buffer/service/mailbox_manager_sync.cc
index 979700a19e38a321f608787bd54735a72b621501..6e860d4eff2cf4da30968f6484e79d5b24b2ad84 100644
--- a/gpu/command_buffer/service/mailbox_manager_sync.cc
+++ b/gpu/command_buffer/service/mailbox_manager_sync.cc
@@ -28,7 +28,7 @@ namespace {
 base::LazyInstance<base::Lock> g_lock = LAZY_INSTANCE_INITIALIZER;
 
 #if !defined(OS_MACOSX)
-typedef std::map<SyncToken, std::unique_ptr<gl::GLFence>> SyncTokenToFenceMap;
+typedef std::map<SyncToken, scoped_refptr<gl::GLFence>> SyncTokenToFenceMap;
 base::LazyInstance<SyncTokenToFenceMap> g_sync_point_to_fence =
     LAZY_INSTANCE_INITIALIZER;
 base::LazyInstance<std::queue<SyncTokenToFenceMap::iterator>> g_sync_points =
@@ -50,10 +50,9 @@ void CreateFenceLocked(const SyncToken& sync_token) {
       sync_points.pop();
     }
     // Need to use EGL fences since we are likely not in a single share group.
-    auto fence = base::MakeUnique<gl::GLFenceEGL>();
+    auto fence = make_scoped_refptr(new gl::GLFenceEGL);
     std::pair<SyncTokenToFenceMap::iterator, bool> result =
-        sync_point_to_fence.insert(
-            std::make_pair(sync_token, std::move(fence)));
+        sync_point_to_fence.insert(std::make_pair(sync_token, fence.get()));
     DCHECK(result.second);
     sync_points.push(result.first);
     DCHECK(sync_points.size() == sync_point_to_fence.size());