cros: Fix browser header wrongly drawn frame image

ui/gfx/canvas.h

 // Copyright (c) 2012 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_GFX_CANVAS_H_
 #define UI_GFX_CANVAS_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 419 matching lines @@
   void DrawSolidFocusRect(RectF rect, SkColor color, int thickness);
 
   // Tiles the image in the specified region.
   // Parameters are specified relative to current canvas scale not in pixels.
   // Thus, |x| is 2 pixels if canvas scale = 2 & |x| = 1.
   void TileImageInt(const ImageSkia& image,
                     int x,
                     int y,
                     int w,
                     int h);
   void TileImageInt(const ImageSkia& image,

[Qiang(Joe) Xu, 2017/03/24 21:55:33]

I still keep the no-flag version since there are some (but not many) callers of
it.

[Peter Kasting, 2017/03/24 22:09:10]

It looks like the three existing functions here have something like 19, 6, and 1
callers, respectively (per codesearch xrefs, which may be inaccurate, but a
glance through the text search results suggests this is close).  I suggest the
following:

* Eliminate the very last function (that takes tile_scale_x/y) as it's just the
internal implementation, and roll its functionality into the second-to-last
function
* Rather than add a new copy here, just add the flags argument to the existing
7-arg function, with a default "= nullptr"

[Qiang(Joe) Xu, 2017/03/24 22:51:05]

Done.

[Qiang(Joe) Xu, 2017/03/28 23:21:07]

We shall not eliminate the last function because of:
https://cs.chromium.org/chromium/src/chrome/browser/ui/views/frame/glass_brow...,
it is compiled for OS_WIN. Do you want a recheck, pkasting@?

                     int src_x,
                     int src_y,
                     int dest_x,
                     int dest_y,
                     int w,
                     int h);
   void TileImageInt(const ImageSkia& image,
                     int src_x,
                     int src_y,
+                    int dest_x,
+                    int dest_y,
+                    int w,
+                    int h,
+                    cc::PaintFlags* flags);
+  void TileImageInt(const ImageSkia& image,
+                    int src_x,
+                    int src_y,
                     float tile_scale_x,
                     float tile_scale_y,
                     int dest_x,
                     int dest_y,
                     int w,
-                    int h);
+                    int h,
+                    cc::PaintFlags* flags);
 
   // Helper for TileImageInt().  Initializes |flags| for tiling |image| with the
   // given parameters.  Returns false if the provided image does not have a
   // representation for the current scale.
   bool InitPaintFlagsForTiling(const ImageSkia& image,
                                int src_x,
                                int src_y,
                                float tile_scale_x,
                                float tile_scale_y,
                                int dest_x,
@@ skipping 50 matching lines @@
   base::Optional<SkBitmap> bitmap_;
   base::Optional<cc::SkiaPaintCanvas> owned_canvas_;
   cc::PaintCanvas* canvas_;
 
   DISALLOW_COPY_AND_ASSIGN(Canvas);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_CANVAS_H_