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

chrome/browser/ui/window_sizer/window_sizer_common_unittest.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/window_sizer/window_sizer_common_unittest.h"
 
 #include "ash/wm/window_resizer.h"
 #include "base/compiler_specific.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/common/chrome_switches.h"
@@ skipping 26 matching lines @@
   return work_areas_[GetMonitorIndexMatchingBounds(match_rect)];
 }
 
 size_t TestMonitorInfoProvider::GetMonitorIndexMatchingBounds(
     const gfx::Rect& match_rect) const {
   int max_area = 0;
   size_t max_area_index = 0;
   // Loop through all the monitors, finding the one that intersects the
   // largest area of the supplied match rect.
   for (size_t i = 0; i < work_areas_.size(); ++i) {
-    gfx::Rect overlap(match_rect.Intersect(work_areas_[i]));
+    gfx::Rect overlap = work_areas_[i];
+    overlap.Intersect(match_rect);
     int area = overlap.width() * overlap.height();
     if (area > max_area) {
       max_area = area;
       max_area_index = i;
     }
   }
   return max_area_index;
 }
 
 TestStateProvider::TestStateProvider():
@@ skipping 320 matching lines @@
   { // Check that a window which hangs out of the screen get moved back in.
     gfx::Rect window_bounds;
     GetWindowBounds(tentwentyfour, tentwentyfour, gfx::Rect(), gfx::Rect(),
                     gfx::Rect(), DEFAULT, NULL,
                     gfx::Rect(1020, 700, 100, 100), &window_bounds);
     EXPECT_EQ("924,668 100x100", window_bounds.ToString());
   }
 }
 
 #endif // defined(OS_MACOSX)