Move ContentBrowserTest class to content/public, since it's used by components_browsertests for bro…

content/test/content_browser_test_utils_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 "content/test/content_browser_test_utils.h"
-
-#include <Carbon/Carbon.h>
-#import <Cocoa/Cocoa.h>
-
-#include "ui/gfx/rect.h"
-
-namespace content {
-
-void SetWindowBounds(gfx::NativeWindow window, const gfx::Rect& bounds) {
-  NSRect new_bounds = NSRectFromCGRect(bounds.ToCGRect());
-  if ([[NSScreen screens] count] > 0) {
-    new_bounds.origin.y =
-        [[[NSScreen screens] objectAtIndex:0] frame].size.height -
-        new_bounds.origin.y - new_bounds.size.height;
-  }
-
-  [window setFrame:new_bounds display:NO];
-}
-
-}  // namespace content