Add non-member non-mutating methods for common gfx::Rect operations.

ui/app_list/search_result_view.cc

 // 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.
 
 #include "ui/app_list/search_result_view.h"
 
 #include "ui/app_list/app_list_constants.h"
 #include "ui/app_list/search_result.h"
 #include "ui/app_list/search_result_list_view.h"
 #include "ui/gfx/canvas.h"
@@ skipping 182 matching lines @@
 
   canvas->FillRect(content_rect, kContentsBackgroundColor);
 
   bool selected = list_view_->IsResultViewSelected(this);
   if (selected) {
     canvas->FillRect(content_rect, kSelectedBackgroundColor);
   } else if (state() == BS_HOT || state() == BS_PUSHED) {
     canvas->FillRect(content_rect, kHoverAndPushedColor);
   }
 
-  gfx::Rect border_bottom(rect);
-  border_bottom.Subtract(content_rect);
+  gfx::Rect border_bottom = gfx::SubtractRects(rect, content_rect);
   canvas->FillRect(border_bottom,
                    selected ? kSelectedBorderColor : kBorderColor);
 
   gfx::Rect text_bounds(rect);
   text_bounds.set_x(kIconViewWidth);
   text_bounds.set_width(
       rect.width() - kIconViewWidth - kTextTrailPadding -
       action_buttons_.size() * kActionButtonWidth -
       (!action_buttons_.empty() ? kActionButtonRightMargin : 0));
   text_bounds.set_x(GetMirroredXWithWidthInView(text_bounds.x(),
@@ skipping 86 matching lines @@
       views::ImageButton* button = action_buttons_[i];
       button->SetImage(views::CustomButton::BS_NORMAL, &icon.base_image);
       button->SetImage(views::CustomButton::BS_HOT, &icon.hover_image);
       button->SetImage(views::CustomButton::BS_PUSHED, &icon.pressed_image);
       button->SetTooltipText(icon.tooltip_text);
     }
   }
 }
 
 }  // namespace app_list