Fix alignment for bubbles with center-arrows.

chrome/browser/ui/cocoa/base_bubble_controller.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.
 
 #import "chrome/browser/ui/cocoa/base_bubble_controller.h"
 
 #include "base/logging.h"
 #include "base/mac/bundle_locations.h"
 #include "base/mac/mac_util.h"
 #include "base/mac/scoped_nsobject.h"
@@ skipping 233 matching lines @@
 // Takes the |anchor_| point and adjusts the window's origin accordingly.
 - (void)updateOriginFromAnchor {
   NSWindow* window = [self window];
   NSPoint origin = anchor_;
 
   switch ([bubble_ alignment]) {
     case info_bubble::kAlignArrowToAnchor: {
       NSSize offsets = NSMakeSize(info_bubble::kBubbleArrowXOffset +
                                   info_bubble::kBubbleArrowWidth / 2.0, 0);
       offsets = [[parentWindow_ contentView] convertSize:offsets toView:nil];
-      if ([bubble_ arrowLocation] == info_bubble::kTopRight) {
-        origin.x -= NSWidth([window frame]) - offsets.width;
-      } else {
-        origin.x -= offsets.width;
+      switch ([bubble_ arrowLocation]) {
+        case info_bubble::kTopRight:
+          origin.x -= NSWidth([window frame]) - offsets.width;
+          break;
+        case info_bubble::kTopLeft:
+          origin.x -= offsets.width;
+          break;
+        case info_bubble::kTopCenter:
+          origin.x -= NSWidth([window frame]) / 2.0;
+          break;
+        case info_bubble::kNoArrow:
+          NOTREACHED();
+          break;
       }
       break;
     }
 
     case info_bubble::kAlignEdgeToAnchorEdge:
       // If the arrow is to the right then move the origin so that the right
       // edge aligns with the anchor. If the arrow is to the left then there's
       // nothing to do because the left edge is already aligned with the left
       // edge of the anchor.
       if ([bubble_ arrowLocation] == info_bubble::kTopRight) {
@@ skipping 19 matching lines @@
 
 - (void)activateTabWithContents:(content::WebContents*)newContents
                previousContents:(content::WebContents*)oldContents
                         atIndex:(NSInteger)index
                          reason:(int)reason {
   // The user switched tabs; close.
   [self close];
 }
 
 @end  // BaseBubbleController