[ios] Remove CWV_IMPLEMENTATION hack in ChromeWebView implementation.

ios/web_view/public/cwv_navigation_action.h

 // Copyright 2017 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_WEB_VIEW_PUBLIC_CWV_NAVIGATION_ACTION_H_
 #define IOS_WEB_VIEW_PUBLIC_CWV_NAVIGATION_ACTION_H_
 
 #import <Foundation/Foundation.h>
 
-// TODO(crbug.com/704946): Make framework style include work everywhere and
-// remove this #if.
-#if defined(CWV_IMPLEMENTATION)
-#include "ios/web_view/public/cwv_export.h"
-#else
-#include <ChromeWebView/cwv_export.h>
-#endif
+#import "cwv_export.h"
 
 // Encapsulates information about an action which caused a navigation.
 CWV_EXPORT
 @interface CWVNavigationAction : NSObject
 
 // Destination request associated with the action.
 @property(nonatomic, copy, readonly, nonnull) NSURLRequest* request;
 // YES if the action was caused by a user action (e.g. link tap).
 @property(nonatomic, readonly, getter=isUserInitiated) BOOL userInitiated;
 
 @end
 
 #endif  // IOS_WEB_VIEW_PUBLIC_CWV_NAVIGATION_ACTION_H_