[ash-md] Eliminates 1px border around overview mode shield

ash/common/wm/overview/window_grid.cc

 // Copyright 2014 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.
 
 #include "ash/common/wm/overview/window_grid.h"
 
 #include <algorithm>
 #include <functional>
 #include <set>
 #include <utility>
@@ skipping 193 matching lines @@
   SetNativeControlColor(background);
 }
 
 void BackgroundWith1PxBorder::Paint(gfx::Canvas* canvas,
                                     views::View* view) const {
   gfx::RectF border_rect_f(view->GetContentsBounds());
 
   gfx::ScopedCanvas scoped_canvas(canvas);
   const float scale = canvas->UndoDeviceScaleFactor();
   border_rect_f.Scale(scale);
-  if (border_thickness_ > 0) {
-    const float inset = border_thickness_ * scale - 0.5f;
-    border_rect_f.Inset(inset, inset);
-  }
+  const float inset = border_thickness_ * scale - 0.5f;
+  border_rect_f.Inset(inset, inset);
 
   SkPath path;
   const SkScalar scaled_corner_radius =
       SkFloatToScalar(corner_radius_ * scale + 0.5f);
   path.addRoundRect(gfx::RectFToSkRect(border_rect_f), scaled_corner_radius,
                     scaled_corner_radius);
 
   SkPaint paint;
   paint.setStyle(SkPaint::kStroke_Style);
   paint.setStrokeWidth(1);
@@ skipping 717 matching lines @@
         *min_right = left;
       if (*max_right < left)
         *max_right = left;
     }
     *max_bottom = top + height;
   }
   return windows_fit;
 }
 
 }  // namespace ash