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

content/browser/renderer_host/render_widget_host_view_win.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 "content/browser/renderer_host/render_widget_host_view_win.h"
 
 #include <algorithm>
 #include <map>
 #include <peninputpanel_i.c>
 #include <stack>
@@ skipping 519 matching lines @@
     SetBrowserAccessibilityManager(
         BrowserAccessibilityManager::CreateEmptyDocument(
             m_hWnd, busy_state, this));
   }
 
   return GetBrowserAccessibilityManager()->GetRoot()->
       ToBrowserAccessibilityWin();
 }
 
 void RenderWidgetHostViewWin::MovePluginWindows(
-    const gfx::Point& scroll_offset,
+    const gfx::Vector2d& scroll_offset,
     const std::vector<webkit::npapi::WebPluginGeometry>& plugin_window_moves) {
   MovePluginWindowsHelper(m_hWnd, plugin_window_moves);
 }
 
 static BOOL CALLBACK AddChildWindowToVector(HWND hwnd, LPARAM lparam) {
   std::vector<HWND>* vector = reinterpret_cast<std::vector<HWND>*>(lparam);
   vector->push_back(hwnd);
   return TRUE;
 }
 
@@ skipping 155 matching lines @@
   // have animations or fairly expensive layout (e.g., google maps).
   //
   // We paint this window synchronously, however child windows (i.e. plugins)
   // are painted asynchronously.  By avoiding synchronous cross-process window
   // message dispatching we allow scrolling to be smooth, and also avoid the
   // browser process locking up if the plugin process is hung.
   //
   RedrawWindow(NULL, damage_region, RDW_UPDATENOW | RDW_NOCHILDREN);
 
   // Send the invalid rect in screen coordinates.
-  gfx::Rect screen_rect = GetViewBounds();
   gfx::Rect invalid_screen_rect(damage_bounds);
-  invalid_screen_rect.Offset(screen_rect.x(), screen_rect.y());
+  invalid_screen_rect.Offset(GetViewBounds().OffsetFromOrigin());
 
   PaintPluginWindowsHelper(m_hWnd, invalid_screen_rect);
 }
 
 void RenderWidgetHostViewWin::DidUpdateBackingStore(
     const gfx::Rect& scroll_rect, int scroll_dx, int scroll_dy,
     const std::vector<gfx::Rect>& copy_rects) {
   if (is_hidden_)
     return;
 
@@ skipping 591 matching lines @@
     if (whiteout_start_time_.is_null())
       whiteout_start_time_ = TimeTicks::Now();
   }
 }
 
 void RenderWidgetHostViewWin::DrawBackground(const RECT& dirty_rect,
                                              CPaintDC* dc) {
   if (!background_.empty()) {
     gfx::Rect dirty_area(dirty_rect);
     gfx::Canvas canvas(dirty_area.size(), ui::SCALE_FACTOR_100P, true);
-    canvas.Translate(gfx::Point().Subtract(dirty_area.origin()));
+    canvas.Translate(gfx::Point() - dirty_area.origin());

[Peter Kasting, 2012/10/31 01:04:41]

Nit: Simpler:

    canvas.Translate(-dirty_area.OffsetFromOrigin());

[danakj, 2012/10/31 16:55:46]

Done.

 
     gfx::Rect dc_rect(dc->m_ps.rcPaint);
     // TODO(pkotwicz): Fix |background_| such that it is an ImageSkia.
     canvas.TileImageInt(gfx::ImageSkia(background_),
                         0, 0, dc_rect.width(), dc_rect.height());
 
     skia::DrawToNativeContext(canvas.sk_canvas(), *dc, dirty_area.x(),
                               dirty_area.y(), NULL);
   } else {
     HBRUSH white_brush = reinterpret_cast<HBRUSH>(GetStockObject(WHITE_BRUSH));
@@ skipping 1673 matching lines @@
   // receive a focus change in the context of a pointer down message, it means
   // that the pointer down message occurred on the edit field and we should
   // display the on screen keyboard
   if (!received_focus_change_after_pointer_down_ && virtual_keyboard_)
     DisplayOnScreenKeyboardIfNeeded();
   received_focus_change_after_pointer_down_ = false;
   pointer_down_context_ = false;
 }
 
 }  // namespace content