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

chrome/browser/ui/cocoa/previewable_contents_controller.h

-// Copyright (c) 2010 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.
-
-#ifndef CHROME_BROWSER_UI_COCOA_PREVIEWABLE_CONTENTS_CONTROLLER_H_
-#define CHROME_BROWSER_UI_COCOA_PREVIEWABLE_CONTENTS_CONTROLLER_H_
-#pragma once
-
-#import <Cocoa/Cocoa.h>
-
-class TabContents;
-
-// PreviewableContentsController manages the display of up to two tab contents
-// views.  It is primarily for use with Instant results.  This class supports
-// the notion of an "active" view vs. a "preview" tab contents view.
-//
-// The "active" view is a container view that can be retrieved using
-// |-activeContainer|.  Its contents are meant to be managed by an external
-// class.
-//
-// The "preview" can be set using |-showPreview:| and |-hidePreview|.  When a
-// preview is set, the active view is hidden (but stays in the view hierarchy).
-// When the preview is removed, the active view is reshown.
-@interface PreviewableContentsController : NSViewController {
- @private
-  // Container view for the "active" contents.
-  IBOutlet NSView* activeContainer_;
-
-  // The preview TabContents.  Will be NULL if no preview is currently showing.
-  TabContents* previewContents_;  // weak
-}
-
-@property(readonly, nonatomic) NSView* activeContainer;
-
-// Sets the current preview and installs its TabContentsView into the view
-// hierarchy.  Hides the active view.  |preview| must not be NULL.
-- (void)showPreview:(TabContents*)preview;
-
-// Closes the current preview and shows the active view.
-- (void)hidePreview;
-
-// Returns YES if the preview contents is currently showing.
-- (BOOL)isShowingPreview;
-
-@end
-
-#endif  // CHROME_BROWSER_UI_COCOA_PREVIEWABLE_CONTENTS_CONTROLLER_H_