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

content/browser/renderer_host/render_widget_host_view_aura.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_aura.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 428 matching lines @@
   return static_cast<gfx::NativeViewId>(NULL);
 #endif
 }
 
 gfx::NativeViewAccessible RenderWidgetHostViewAura::GetNativeViewAccessible() {
   NOTIMPLEMENTED();
   return static_cast<gfx::NativeViewAccessible>(NULL);
 }
 
 void RenderWidgetHostViewAura::MovePluginWindows(
-    const gfx::Point& scroll_offset,
+    const gfx::Vector2d& scroll_offset,
     const std::vector<webkit::npapi::WebPluginGeometry>& plugin_window_moves) {
 #if defined(OS_WIN)
   // We need to clip the rectangle to the tab's viewport, otherwise we will draw
   // over the browser UI.
   if (!window_->GetRootWindow()) {
     DCHECK(plugin_window_moves.empty());
     return;
   }
   HWND parent = window_->GetRootWindow()->GetAcceleratedWidget();
   gfx::Rect view_bounds = window_->GetBoundsInRootWindow();
   std::vector<webkit::npapi::WebPluginGeometry> moves = plugin_window_moves;
 
   gfx::Rect view_port(scroll_offset.x(), scroll_offset.y(), view_bounds.width(),
                       view_bounds.height());
 
   for (size_t i = 0; i < moves.size(); ++i) {
     gfx::Rect clip = moves[i].clip_rect;
-    clip.Offset(moves[i].window_rect.origin());
-    clip.Offset(scroll_offset);
+    clip.Offset(moves[i].window_rect.OffsetFromOrigin() + scroll_offset);

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

One other possible way to do this I didn't think of:

    const gfx::Vector2d offset(
        moves[i].window_rect.OffsetFromOrigin() + scroll_offset);
    clip.Offset(offset);
    ...
    clip.Offset(-offset);

This is two lines longer but possibly clearer and less error-prone.  I'm
ambivalent, do whichever you like better.

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

I like temp vars :) I'll do this.

     clip.Intersect(view_port);
-    clip.Offset(-moves[i].window_rect.x(), -moves[i].window_rect.y());
-    clip.Offset(-scroll_offset.x(), -scroll_offset.y());
+    clip.Offset(-moves[i].window_rect.OffsetFromOrigin() - scroll_offset);
     moves[i].clip_rect = clip;
 
-    moves[i].window_rect.Offset(view_bounds.origin());
+    moves[i].window_rect.Offset(view_bounds.OffsetFromOrigin());
   }
   MovePluginWindowsHelper(parent, moves);
 
   // Make sure each plugin window (or its wrapper if it exists) has a pointer to
   // |this|.
   for (size_t i = 0; i < moves.size(); ++i) {
     HWND window = moves[i].window;
     if (GetParent(window) != parent) {
       window = GetParent(window);
       DCHECK(GetParent(window) == parent);
@@ skipping 1431 matching lines @@
     RenderWidgetHost* widget) {
   return new RenderWidgetHostViewAura(widget);
 }
 
 // static
 void RenderWidgetHostViewPort::GetDefaultScreenInfo(WebScreenInfo* results) {
   GetScreenInfoForWindow(results, NULL);
 }
 
 }  // namespace content