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

ash/tooltips/tooltip_controller.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 "ash/tooltips/tooltip_controller.h"
 
 #include <vector>
 
 #include "ash/ash_switches.h"
 #include "ash/shell.h"
@@ skipping 432 matching lines @@
   // want to update the tooltip because the timer has fired.
   // If we come here from UpdateTooltip(), we have already checked for tooltip
   // visibility and this check below will have no effect.
   if (tooltip_text_ != tooltip_text || !GetTooltip()->IsVisible()) {
     tooltip_shown_timer_.Stop();
     tooltip_text_ = tooltip_text;
     if (tooltip_text_.empty()) {
       GetTooltip()->Hide();
     } else {
       string16 tooltip_text(tooltip_text_);
-      gfx::Point widget_loc = curr_mouse_loc_;
-      widget_loc = widget_loc.Add(
-          tooltip_window_->GetBoundsInScreen().origin());
+      gfx::Point widget_loc = curr_mouse_loc_.Add(
+          tooltip_window_->GetBoundsInScreen().OffsetFromOrigin());
       GetTooltip()->SetText(tooltip_text, widget_loc);
       GetTooltip()->Show();
       tooltip_shown_timer_.Start(FROM_HERE,
           base::TimeDelta::FromMilliseconds(kTooltipShownTimeoutMs),
           this, &TooltipController::TooltipShownTimerFired);
     }
   }
 }
 
 bool TooltipController::IsTooltipVisible() {
   return GetTooltip()->IsVisible();
 }
 
 bool TooltipController::IsDragDropInProgress() {
   return drag_drop_client_->IsDragDropInProgress();
 }
 
 TooltipController::Tooltip* TooltipController::GetTooltip() {
   if (!tooltip_.get())
     tooltip_.reset(new Tooltip);
   return tooltip_.get();
 }
 
 }  // namespace internal
 }  // namespace ash