Add Vector2d classes that represent offsets, instead of using Point.

chrome/browser/ui/gtk/tabs/tab_renderer_gtk.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 "chrome/browser/ui/gtk/tabs/tab_renderer_gtk.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/debug/trace_event.h"
@@ skipping 75 matching lines @@
 
 // Duration for when the title of an inactive mini-tab changes.
 const int kMiniTitleChangeThrobDuration = 1000;
 
 // The horizontal offset used to position the close button in the tab.
 const int kCloseButtonHorzFuzz = 4;
 
 // Gets the bounds of |widget| relative to |parent|.
 gfx::Rect GetWidgetBoundsRelativeToParent(GtkWidget* parent,
                                           GtkWidget* widget) {
-  gfx::Point parent_pos = ui::GetWidgetScreenPosition(parent);
-  gfx::Point widget_pos = ui::GetWidgetScreenPosition(widget);
+  gfx::Vector2d parent_offset = ui::GetWidgetScreenOffset(parent);
+  gfx::Vector2d widget_offset = ui::GetWidgetScreenOffset(widget);
+  gfx::Vector2d offset_from_parent = widget_offset - parent_offset;
 
   GtkAllocation allocation;
   gtk_widget_get_allocation(widget, &allocation);
 
-  return gfx::Rect(widget_pos.x() - parent_pos.x(),
-                   widget_pos.y() - parent_pos.y(),
-                   allocation.width, allocation.height);
+  return gfx::Rect(gfx::PointAtOffsetFromOrigin(offset_from_parent),
+                   gfx::Size(allocation.width, allocation.height));

[Peter Kasting, 2012/10/29 23:06:33]

Nit: Assuming your earlier use of GetWidgetScreenBounds works correctly, seems
like this could use a similar trick to be condensed to something like:

  gfx::Rect bounds(ui::GetWidgetScreenBounds(widget));
  bounds.Offset(-ui::GetWidgetScreenOffset(parent));
  return bounds;

(Collapses to one line once we have Rect:operator+())

[danakj, 2012/10/29 23:21:41]

Done.

 }
 
 }  // namespace
 
 TabRendererGtk::LoadingAnimation::Data::Data(
     GtkThemeService* theme_service) {
   // The loading animation image is a strip of states. Each state must be
   // square, so the height must divide the width evenly.
   SkBitmap loading_animation_frames =
       theme_service->GetImageNamed(IDR_THROBBER).AsBitmap();
@@ skipping 1006 matching lines @@
   GdkPixbuf* tab_close = rb.GetNativeImageNamed(IDR_TAB_CLOSE).ToGdkPixbuf();
   close_button_width_ = gdk_pixbuf_get_width(tab_close);
   close_button_height_ = gdk_pixbuf_get_height(tab_close);
 
   const gfx::Font& base_font = rb.GetFont(ui::ResourceBundle::BaseFont);
   title_font_ = new gfx::Font(base_font.GetFontName(), kFontPixelSize);
   title_font_height_ = title_font_->GetHeight();
 
   initialized_ = true;
 }