Added methods to generate sync tokens for resource id(s).

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index 1bcd37d9ebee30efc08f3fb6526b97db592e6899..bd759da8f9c190d1ca033345bfed67d51d391178 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -3648,6 +3648,8 @@ void LayerTreeHostImpl::CreateUIResource(UIResourceId uid,
   AutoLockUIResourceBitmap bitmap_lock(bitmap);
   resource_provider_->CopyToResource(id, bitmap_lock.GetPixels(),
                                      bitmap.GetSize());
+
+  resource_provider_->GenerateSyncTokenForResource(id);
   MarkUIResourceNotEvicted(uid);
 }