Improve painting of cros tray separators.

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 261 matching lines @@
   void DrawPoint(const Point& p, const cc::PaintFlags& flags);
 
   // Draw the given point with the given |flags| parameters.
   void DrawPoint(const PointF& p, const cc::PaintFlags& flags);
 
   // Draws a single pixel line with the specified color.
   // DEPRECATED in favor of the RectF version below.
   // TODO(funkysidd): Remove this (http://crbug.com/553726)
   void DrawLine(const Point& p1, const Point& p2, SkColor color);
 
-  // Draws a single pixel line with the specified color.
+  // Draws a single dip line with the specified color.
   void DrawLine(const PointF& p1, const PointF& p2, SkColor color);
 
   // Draws a line with the given |flags| parameters.
   // DEPRECATED in favor of the RectF version below.
   // TODO(funkysidd): Remove this (http://crbug.com/553726)
   void DrawLine(const Point& p1, const Point& p2, const cc::PaintFlags& flags);
 
   // Draws a line with the given |flags| parameters.
   void DrawLine(const PointF& p1,
                 const PointF& p2,
                 const cc::PaintFlags& flags);
 
   // Draws a line that's a single DIP. At fractional scale factors, this is
   // floored to the nearest integral number of pixels.
   void DrawSharpLine(PointF p1, PointF p2, SkColor color);
 
+  // As above, but draws a single pixel at all scale factors.
+  void Draw1pxLine(PointF p1, PointF p2, SkColor color);
+
   // Draws a circle with the given |flags| parameters.
   // DEPRECATED in favor of the RectF version below.
   // TODO(funkysidd): Remove this (http://crbug.com/553726)
   void DrawCircle(const Point& center_point,
                   int radius,
                   const cc::PaintFlags& flags);
 
   // Draws a circle with the given |flags| parameters.
   void DrawCircle(const PointF& center_point,
                   float radius,
@@ skipping 203 matching lines @@
   // but surface_ will be null.
   sk_sp<cc::PaintSurface> surface_;
   cc::PaintCanvas* canvas_;
 
   DISALLOW_COPY_AND_ASSIGN(Canvas);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_CANVAS_H_