Create c/b/ui/cocoa/test and move test files to there

chrome/browser/ui/cocoa/styled_text_field_test_helper.mm

Index: chrome/browser/ui/cocoa/styled_text_field_test_helper.mm
diff --git a/chrome/browser/ui/cocoa/styled_text_field_test_helper.mm b/chrome/browser/ui/cocoa/styled_text_field_test_helper.mm
deleted file mode 100644
index 20f566df98874f795d45ed327605900de2900ceb..0000000000000000000000000000000000000000
--- a/chrome/browser/ui/cocoa/styled_text_field_test_helper.mm
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright (c) 2009 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 <Cocoa/Cocoa.h>
-#import "chrome/browser/ui/cocoa/styled_text_field_test_helper.h"
-
-@implementation StyledTextFieldTestCell
-@synthesize leftMargin = leftMargin_;
-@synthesize rightMargin = rightMargin_;
-
-- (NSRect)textFrameForFrame:(NSRect)frame {
-  NSRect textFrame = [super textFrameForFrame:frame];
-  textFrame.origin.x += leftMargin_;
-  textFrame.size.width -= (leftMargin_ + rightMargin_);
-  return textFrame;
-}
-@end