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

chrome/browser/ui/cocoa/autofill/autofill_textfield_unittest.mm

 // Copyright (c) 2013 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/autofill/autofill_textfield.h"
 
 #import "base/mac/scoped_nsobject.h"
 #include "base/macros.h"
-#import "chrome/browser/ui/cocoa/cocoa_test_helper.h"
+#import "chrome/browser/ui/cocoa/test/cocoa_test_helper.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/gtest_mac.h"
 #include "testing/platform_test.h"
 #include "ui/events/test/cocoa_test_event_utils.h"
 
 class AutofillTextFieldTest : public CocoaTest {
  public:
   AutofillTextFieldTest() {
     NSRect frame = NSMakeRect(0, 0, 50, 30);
     textfield_.reset([[AutofillTextField alloc] initWithFrame:frame]);
@@ skipping 49 matching lines @@
 
   // Now test with multiline mode enabled.
   [textfield_ setIsMultiline:YES];
   [textfield_ setStringValue:@""];
   [[textfield_ currentEditor] insertText:@"foo"];
   [[textfield_ currentEditor]
       keyDown:cocoa_test_event_utils::KeyEventWithCharacter('\n')];
   [[textfield_ currentEditor] insertText:@"bar"];
   EXPECT_NSEQ(@"foo\nbar", [textfield_ stringValue]);
 }