[Mac] M6 Omnibox positioning changes.

chrome/browser/cocoa/location_bar/image_decoration.mm

 // Copyright (c) 2010 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 <cmath>
 
 #import "chrome/browser/cocoa/location_bar/image_decoration.h"
 
 #import "chrome/browser/cocoa/image_utils.h"
 
 ImageDecoration::ImageDecoration() {
 }
 
 ImageDecoration::~ImageDecoration() {
 }
 
 NSImage* ImageDecoration::GetImage() {
   return image_;
 }
 
 void ImageDecoration::SetImage(NSImage* image) {
   image_.reset([image retain]);
 }
 
 NSRect ImageDecoration::GetDrawRectInFrame(NSRect frame) {
   NSImage* image = GetImage();
   if (!image)
     return frame;
 
+  // Center the image within the frame.
   const CGFloat delta_height = NSHeight(frame) - [image size].height;
   const CGFloat y_inset = std::floor(delta_height / 2.0);
-  return NSInsetRect(frame, 0.0, y_inset);
+  const CGFloat delta_width = NSWidth(frame) - [image size].width;
+  const CGFloat x_inset = std::floor(delta_width / 2.0);
+  return NSInsetRect(frame, x_inset, y_inset);
 }
 
 CGFloat ImageDecoration::GetWidthForSpace(CGFloat width) {
   NSImage* image = GetImage();
   if (image) {
     const CGFloat image_width = [image size].width;
     if (image_width <= width)
       return image_width;
   }
   return kOmittedWidth;
 }
 
 void ImageDecoration::DrawInFrame(NSRect frame, NSView* control_view) {
   [GetImage() drawInRect:GetDrawRectInFrame(frame)
                 fromRect:NSZeroRect  // Entire image
                operation:NSCompositeSourceOver
                 fraction:1.0
             neverFlipped:YES];
 }