Upstream Chrome on iOS source code [9/11].

ios/chrome/browser/ui/toolbar/toolbar_owner.h

+// Copyright 2014 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 IOS_CHROME_BROWSER_UI_TOOLBAR_TOOLBAR_OWNER_H_
+#define IOS_CHROME_BROWSER_UI_TOOLBAR_TOOLBAR_OWNER_H_
+
+#import <Foundation/Foundation.h>
+
+@class ToolbarController;
+
+@protocol ToolbarOwner<NSObject>
+
+// Returns a reference to the toolbar controller so that it can be included in
+// animations. Calls should be paired with calls to |-reparentToolbarController|
+// when the relinquished toolbar controller is no longer needed by the caller.
+// Returns nil if called when the toolbar has already been relinquished.
+- (ToolbarController*)relinquishedToolbarController;
+// Reparents the toolbar into its place in the view hierarchy before it was
+// relinquished.
+- (void)reparentToolbarController;
+
+@optional
+// Returns the height of the toolbar owned by the implementing class.
+- (CGFloat)toolbarHeight;
+
+@end
+
+#endif  // IOS_CHROME_BROWSER_UI_TOOLBAR_TOOLBAR_OWNER_H_