mac: Use convertSizeFromBacking: instead of the deprecated ...FromBase:

ui/gfx/screen_mac.mm

 // 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 "ui/gfx/screen.h"
 
 #import <ApplicationServices/ApplicationServices.h>
 #import <Cocoa/Cocoa.h>
 
+#include "base/logging.h"
+#include "ui/gfx/display.h"
+
+#if !defined(MAC_OS_X_VERSION_10_7) || \
+    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_7
+
 @interface NSScreen (LionAPI)
 - (CGFloat)backingScaleFactor;
 @end
 
-#include "base/logging.h"
-#include "ui/gfx/display.h"
+#endif  // 10.7
 
 namespace {
 
 gfx::Rect ConvertCoordinateSystem(NSRect ns_rect) {
   // Primary monitor is defined as the monitor with the menubar,
   // which is always at index 0.
   NSScreen* primary_screen = [[NSScreen screens] objectAtIndex:0];
   float primary_screen_height = [primary_screen frame].size.height;
   gfx::Rect rect(NSRectToCGRect(ns_rect));
   rect.set_y(primary_screen_height - rect.y() - rect.height());
@@ skipping 128 matching lines @@
   NSArray* screens = [NSScreen screens];
   NSScreen* primary = [screens objectAtIndex:0];
   for (NSScreen* screen in screens) {
     if (NSMouseInRect(ns_point, [screen frame], NO))
       return GetDisplayForScreen(screen, screen == primary);
   }
   return GetPrimaryDisplay();
 }
 
 }  // namespace gfx