Add a histogram to measure browser window display

chrome/browser/ui/cocoa/simple_message_box_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 "chrome/browser/ui/simple_message_box.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/sys_string_conversions.h"
+#include "chrome/common/startup_metric_utils.h"
 #include "grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util_mac.h"
 
 namespace chrome {
 
 MessageBoxResult ShowMessageBox(gfx::NativeWindow parent,
                                 const string16& title,
                                 const string16& message,
                                 MessageBoxType type) {
+  startup_metric_utils::SetNonBrowserUIDisplayed();
+
   // Ignore the title; it's the window title on other platforms and ignorable.
   NSAlert* alert = [[[NSAlert alloc] init] autorelease];
   [alert setMessageText:base::SysUTF16ToNSString(message)];
   NSUInteger style = (type == MESSAGE_BOX_TYPE_INFORMATION) ?
       NSInformationalAlertStyle : NSWarningAlertStyle;
   [alert setAlertStyle:style];
   if (type == MESSAGE_BOX_TYPE_QUESTION) {
     [alert addButtonWithTitle:
         l10n_util::GetNSString(IDS_CONFIRM_MESSAGEBOX_YES_BUTTON_LABEL)];
     [alert addButtonWithTitle:
         l10n_util::GetNSString(IDS_CONFIRM_MESSAGEBOX_NO_BUTTON_LABEL)];
   } else {
     [alert addButtonWithTitle:l10n_util::GetNSString(IDS_OK)];
   }
   NSInteger result = [alert runModal];
   return (result == NSAlertSecondButtonReturn) ?
       MESSAGE_BOX_RESULT_NO : MESSAGE_BOX_RESULT_YES;
 }
 
 }  // namespace chrome