Reuse context menu in StaticHTMLViewController

ios/web/public/web_view_creation_util.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_PUBLIC_WEB_VIEW_CREATION_UTIL_H_
 #define IOS_WEB_PUBLIC_WEB_VIEW_CREATION_UTIL_H_
 
 #import <CoreGraphics/CoreGraphics.h>
 #import <Foundation/Foundation.h>
 
+@protocol CRWContextMenuDelegate;
 @class WKWebView;
 
 namespace web {
 class BrowserState;
 
 // Returns a new WKWebView for displaying regular web content.
 // WKWebViewConfiguration object for resulting web view will be obtained from
 // the given |browser_state|.
 //
 // Preconditions for creation of a WKWebView:
 // 1) |browser_state| is not null.
 // 2) web::BrowsingDataPartition is synchronized.
 //
 WKWebView* BuildWKWebView(CGRect frame, BrowserState* browser_state);
 
+// Returns a new WKWebView for displaying regular web content.
+// The returned WKWebView is equivalent to the one created by |BuildWKWebView|
+// but a context menu recognizer is attached to it.
+// On a long press, context_menu_delegate webView:handleContextMenu:| is called.
+// Calling |BuildWKWebViewWithCustomContextMenu| with a |context_menu_delegate|
+// nil is equivalent to |BuildWKWebView|.

[Eugene But (OOO till 7-30), 2017/01/13 16:19:41]

Attaching content menu recognized has an actual performance implications (JS
will be executed on literally every touch). Please document that, so clients are
aware about performance tradeoff. 

[Olivier, 2017/01/13 18:08:58]

Done.

+WKWebView* BuildWKWebViewWithCustomContextMenu(
+    CGRect frame,
+    BrowserState* browser_state,
+    id<CRWContextMenuDelegate> context_menu_delegate);
+
 }  // web
 
 #endif  // IOS_WEB_PUBLIC_WEB_VIEW_CREATION_UTIL_H_