Add a few missing &s.

ui/gl/ca_renderer_layer_params.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_GL_CA_RENDERER_LAYER_PARAMS_H_
 #define UI_GL_CA_RENDERER_LAYER_PARAMS_H_
 
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/rect_f.h"
 #include "ui/gfx/transform.h"
 #include "ui/gl/gl_export.h"
 
 namespace gl {
 class GLImage;
 }
 
 namespace ui {
 
 struct GL_EXPORT CARendererLayerParams {
   CARendererLayerParams(bool is_clipped,
                         const gfx::Rect clip_rect,
                         unsigned sorting_context_id,
-                        const gfx::Transform transform,
+                        const gfx::Transform& transform,
                         gl::GLImage* image,
-                        const gfx::RectF contents_rect,
-                        const gfx::Rect rect,
+                        const gfx::RectF& contents_rect,
+                        const gfx::Rect& rect,
                         unsigned background_color,
                         unsigned edge_aa_mask,
                         float opacity,
                         unsigned filter);
   CARendererLayerParams(const CARendererLayerParams& other);
   ~CARendererLayerParams();
 
   bool is_clipped;
   const gfx::Rect clip_rect;
   unsigned sorting_context_id;
   const gfx::Transform transform;
   gl::GLImage* image;
   const gfx::RectF contents_rect;
   const gfx::Rect rect;
   unsigned background_color;
   unsigned edge_aa_mask;
   float opacity;
   unsigned filter;
 };
 
 }  // namespace ui
 
 #endif  // UI_GL_CA_RENDERER_LAYER_PARAMS_H_