[ObjC ARC] Converts ios/chrome/browser/ui/find_bar:find_bar to ARC.

ios/chrome/browser/ui/find_bar/find_bar_view.h

 // Copyright 2016 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_FIND_BAR_FIND_BAR_VIEW_H_
 #define IOS_CHROME_BROWSER_UI_FIND_BAR_FIND_BAR_VIEW_H_
 
 #import <UIKit/UIKit.h>
 
 // The a11y ID of the text input field in the find-in-page bar.
@@ skipping 20 matching lines @@
     NS_DESIGNATED_INITIALIZER;
 
 - (instancetype)initWithFrame:(CGRect)frame NS_UNAVAILABLE;
 - (instancetype)initWithCoder:(NSCoder*)aDecoder NS_UNAVAILABLE;
 
 // Updates |resultsLabel| with |text|. Updates |inputField| layout so that input
 // text does not overlap with results count. |text| can be nil.
 - (void)updateResultsLabelWithText:(NSString*)text;
 
 // The textfield with search term.
-@property(nonatomic, assign) UITextField* inputField;
+@property(nonatomic, weak) UITextField* inputField;
 // Button to go to previous search result.
-@property(nonatomic, assign) UIButton* previousButton;
+@property(nonatomic, weak) UIButton* previousButton;
 // Button to go to next search result.
-@property(nonatomic, assign) UIButton* nextButton;
+@property(nonatomic, weak) UIButton* nextButton;
 // Button to dismiss Find in Page.
-@property(nonatomic, assign) UIButton* closeButton;
+@property(nonatomic, weak) UIButton* closeButton;
 
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_FIND_BAR_FIND_BAR_VIEW_H_