Make gfx::Rect class operations consistently mutate the class they are called on.

content/renderer/disambiguation_popup_helper.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/renderer/disambiguation_popup_helper.h"
 
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebRect.h"
 #include "ui/gfx/size_conversions.h"
 
 using WebKit::WebRect;
@@ skipping 74 matching lines @@
 
 namespace content {
 
 float DisambiguationPopupHelper::ComputeZoomAreaAndScaleFactor(
     const gfx::Rect& tap_rect,
     const WebVector<WebRect>& target_rects,
     const gfx::Size& viewport_size,
     gfx::Rect* zoom_rect) {
   *zoom_rect = tap_rect;
   for (size_t i = 0; i < target_rects.size(); i++)
-    *zoom_rect = zoom_rect->Union(gfx::Rect(target_rects[i]));
+    zoom_rect->Union(gfx::Rect(target_rects[i]));
   zoom_rect->Inset(-kDisambiguationPopupPadding, -kDisambiguationPopupPadding);
-  *zoom_rect = zoom_rect->Intersect(gfx::Rect(viewport_size));
+  zoom_rect->Intersect(gfx::Rect(viewport_size));
 
   float scale = FindOptimalScaleFactor(target_rects);
   *zoom_rect = CropZoomArea(
       *zoom_rect, viewport_size, tap_rect.CenterPoint(), scale);
 
   return scale;
 }
 
 } // namespace content