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

ios/chrome/browser/ui/tab_switcher/tab_switcher_panel_view.h

+// Copyright 2015 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_TAB_SWITCHER_TAB_SWITCHER_PANEL_VIEW_H_
+#define IOS_CHROME_BROWSER_UI_TAB_SWITCHER_TAB_SWITCHER_PANEL_VIEW_H_
+
+#import <UIKit/UIKit.h>
+
+#import "ios/chrome/browser/ui/tab_switcher/tab_switcher_model.h"
+
+@class TabSwitcherCache;
+
+@interface TabSwitcherPanelView : UIView
+
+@property(nonatomic, readonly) UICollectionView* collectionView;
+
+- (instancetype)initWithSessionType:(ios_internal::SessionType)sessionType
+    NS_DESIGNATED_INITIALIZER;
+
+- (instancetype)initWithFrame:(CGRect)frame NS_UNAVAILABLE;
+- (instancetype)initWithCoder:(NSCoder*)aDecoder NS_UNAVAILABLE;
+
+// Updates the collectionView's layout to ensure that the optimal amount of tabs
+// are displayed. The completion block is called at the end of the layout
+// update.
+- (void)updateCollectionLayoutWithCompletion:(void (^)(void))completion;
+
+// Returns the size of the cells displayed in the collectionView.
+- (CGSize)cellSize;
+
+@end
+
+#endif  // IOS_CHROME_BROWSER_UI_TAB_SWITCHER_TAB_SWITCHER_PANEL_VIEW_H_