[Mac] Organize some files into chrome/browser/ui/cocoa/tab_contents/....

chrome/browser/ui/cocoa/sad_tab_view_unittest.mm

-// 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 "chrome/browser/ui/cocoa/sad_tab_view.h"
-#import "chrome/browser/ui/cocoa/cocoa_test_helper.h"
-
-namespace {
-
-class SadTabViewTest : public CocoaTest {
- public:
-  SadTabViewTest() {
-    NSRect content_frame = [[test_window() contentView] frame];
-    scoped_nsobject<SadTabView> view([[SadTabView alloc]
-                                      initWithFrame:content_frame]);
-    view_ = view.get();
-    [[test_window() contentView] addSubview:view_];
-  }
-
-  SadTabView* view_;  // Weak. Owned by the view hierarchy.
-};
-
-TEST_VIEW(SadTabViewTest, view_);
-
-}  // namespace