Add machinery to show touch editing context menus in OOPIFs.

third_party/WebKit/Source/web/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 3482 matching lines @@
   if (!menu)
     return;
   const ContextMenuItem* item = menu->ItemWithAction(
       static_cast<ContextMenuAction>(kContextMenuItemBaseCustomTag + action));
   if (item)
     page_->GetContextMenuController().ContextMenuItemSelected(item);
   page_->GetContextMenuController().ClearContextMenu();
 }
 
 void WebViewImpl::ShowContextMenu(WebMenuSourceType source_type) {
-  if (!GetPage())
+  if (!MainFrameImpl())
     return;
 
-  GetPage()->GetContextMenuController().ClearContextMenu();
-  {
-    ContextMenuAllowedScope scope;
-    if (LocalFrame* focused_frame = ToLocalFrame(
-            GetPage()->GetFocusController().FocusedOrMainFrame())) {
-      focused_frame->GetEventHandler().ShowNonLocatedContextMenu(nullptr,
-                                                                 source_type);
-    }
-  }
+  // If MainFrameImpl() is non-null, then FrameWidget() will also be non-null.
+  DCHECK(MainFrameImpl()->FrameWidget());
+  MainFrameImpl()->FrameWidget()->ShowContextMenu(source_type);

[dcheng, 2017/05/26 18:22:27]

This frame widget is actually a WebViewFrameWidget. Since the default on
WebWidget is unimplemented, that means this won't do anything.

If we want to share behavior, I guess we should:
- move the method to WebFrameWidget instead of WebWidget
- put the original logic WebFrameWidgetBase and have WebViewFrameWidget and
WebFrameWidgetImpl both delegate to it.

WDYT?

 }
 
 void WebViewImpl::DidCloseContextMenu() {
   LocalFrame* frame = page_->GetFocusController().FocusedFrame();
   if (frame)
     frame->Selection().SetCaretBlinkingSuspended(false);
 }
 
 void WebViewImpl::HidePopups() {
   CancelPagePopup();
@@ skipping 632 matching lines @@
   if (focused_frame->LocalFrameRoot() != MainFrameImpl()->GetFrame())
     return nullptr;
   return focused_frame;
 }
 
 LocalFrame* WebViewImpl::FocusedLocalFrameAvailableForIme() const {
   return ime_accept_events_ ? FocusedLocalFrameInWidget() : nullptr;
 }
 
 }  // namespace blink