[ios] Remove CWV_IMPLEMENTATION hack in ChromeWebView implementation.

ios/web_view/internal/web_view_web_main_parts.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_WEB_VIEW_INTERNAL_WEB_VIEW_WEB_MAIN_PARTS_H_
 #define IOS_WEB_VIEW_INTERNAL_WEB_VIEW_WEB_MAIN_PARTS_H_
 
+#include <memory>
+
 #include "ios/web/public/app/web_main_parts.h"
 
-#include <memory>
-
 @protocol CWVDelegate;
 
 namespace ios_web_view {
 class WebViewBrowserState;
 
 // WebView implementation of WebMainParts.
 class WebViewWebMainParts : public web::WebMainParts {
  public:
   explicit WebViewWebMainParts(id<CWVDelegate> delegate);
   ~WebViewWebMainParts() override;
@@ skipping 16 matching lines @@
   // The BrowserState for this embedder.
   std::unique_ptr<WebViewBrowserState> browser_state_;
 
   // Off The Record BrowserState for this embedder.
   std::unique_ptr<WebViewBrowserState> off_the_record_browser_state_;
 };
 
 }  // namespace ios_web_view
 
 #endif  // IOS_WEB_VIEW_INTERNAL_WEB_VIEW_WEB_MAIN_PARTS_H_