cc: Fix a bug of preventing conversion from non-tiled mask to tiled mask.

cc/layers/picture_layer.cc

Index: cc/layers/picture_layer.cc
diff --git a/cc/layers/picture_layer.cc b/cc/layers/picture_layer.cc
index 7c1502085e997d7e2c41486ce17238913a51770c..68e92f74f9ffacb7a84a055c46b21ab1b93980e1 100644
--- a/cc/layers/picture_layer.cc
+++ b/cc/layers/picture_layer.cc
@@ -149,7 +149,7 @@ void PictureLayer::SetLayerMaskType(LayerMaskType mask_type) {
   // We do not allow converting SINGLE_TEXTURE_MASK to MULTI_TEXTURE_MASK in
   // order to avoid rerastering when a mask's transform is being animated.
   if (mask_type_ == LayerMaskType::SINGLE_TEXTURE_MASK &&
-      LayerMaskType::MULTI_TEXTURE_MASK)
+      mask_type == LayerMaskType::MULTI_TEXTURE_MASK)
     return;
   mask_type_ = mask_type;
 }