Reland of [ObjC ARC] Converts ios/chrome/browser/ui/contextual_search:contextual_search to ARC.

ios/chrome/browser/ui/contextual_search/contextual_search_panel_view.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_CONTEXTUAL_SEARCH_CONTEXTUAL_SEARCH_PANEL_VIEW_H_
 #define IOS_CHROME_BROWSER_UI_CONTEXTUAL_SEARCH_CONTEXTUAL_SEARCH_PANEL_VIEW_H_
 
 #import <UIKit/UIKit.h>
 #import "ios/chrome/browser/ui/contextual_search/panel_configuration.h"
 
 @protocol ContextualSearchPanelMotionObserver;
 @protocol ContextualSearchPanelTapHandler;
 
 // A view designed to sit "on top" of the frontmost tab in a range of positions,
 // with content can position controlled by a ContextualSearchPanelController.
 // Generally speaking each BrowserViewController will own both the panel view
 // and panel controller object.
 @interface ContextualSearchPanelView : UIView
 
 // Current state.
 @property(nonatomic, assign) ContextualSearch::PanelState state;
 // Panel configuration, for motion observers that want to do different
 // computations around panel state and position.
-@property(nonatomic, readonly) PanelConfiguration* configuration;
+@property(nonatomic, strong, readonly) PanelConfiguration* configuration;
 
 // Create a panel view. It will need to have a delegate and controller assigned
 // to do anything useful.
 - (instancetype)initWithConfiguration:(PanelConfiguration*)configuration
     NS_DESIGNATED_INITIALIZER;
 
 - (instancetype)initWithCoder:(NSCoder*)aDecoder NS_UNAVAILABLE;
 
 - (instancetype)initWithFrame:(CGRect)frame NS_UNAVAILABLE;
 
@@ skipping 11 matching lines @@
 
 // Inform the receiver it is about to promote to be tab-sized; it will inform
 // any obsevers.
 - (void)prepareForPromotion;
 // Have the receiver adjust its frame to match its superview's bounds,
 // vertically offset by |offset| points from the y-origin.
 - (void)promoteToMatchSuperviewWithVerticalOffset:(CGFloat)offset;
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_CONTEXTUAL_SEARCH_CONTEXTUAL_SEARCH_PANEL_VIEW_H_