Move CrTrackingArea from chrome/browser/ui/cocoa to ui/base/cocoa.

ui/base/cocoa/tracking_area_unittest.mm

 // Copyright (c) 2011 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 "base/memory/scoped_nsobject.h"
-#include "chrome/browser/ui/cocoa/cocoa_test_helper.h"
-#import "chrome/browser/ui/cocoa/tracking_area.h"
+#import "ui/base/cocoa/tracking_area.h"
+#import "ui/base/test/ui_cocoa_test_helper.h"
 
 // A test object that counts the number of times a message is sent to it.
 @interface TestTrackingAreaOwner : NSObject {
  @private
   NSUInteger messageCount_;
 }
 @property(nonatomic, assign) NSUInteger messageCount;
 - (void)performMessage;
 @end
 
 @implementation TestTrackingAreaOwner
 @synthesize messageCount = messageCount_;
 - (void)performMessage {
   ++messageCount_;
 }
 @end
 
+namespace ui {
+
 class CrTrackingAreaTest : public CocoaTest {
  public:
   CrTrackingAreaTest()
       : owner_([[TestTrackingAreaOwner alloc] init]),
         trackingArea_([[CrTrackingArea alloc]
             initWithRect:NSMakeRect(0, 0, 100, 100)
                  options:NSTrackingMouseMoved | NSTrackingActiveInKeyWindow
                    owner:owner_.get()
                 userInfo:nil]) {
   }
@@ skipping 53 matching lines @@
     [[scoper.get() owner] performMessage];
     EXPECT_EQ(1U, [owner_ messageCount]);
 
     [[scoper.get() owner] performMessage];
     EXPECT_EQ(2U, [owner_ messageCount]);
   }
 
   [[trackingArea_ owner] performMessage];
   EXPECT_EQ(2U, [owner_ messageCount]);
 }
+
+}  // namespace ui