Add machinery to show touch editing context menus in OOPIFs.

content/renderer/render_widget.cc

Index: content/renderer/render_widget.cc
diff --git a/content/renderer/render_widget.cc b/content/renderer/render_widget.cc
index ce810c1bcf38dcc16975d046ca1ee559b01eaf69..4d79df6b9d8b28932f0123dc948ff11bb6eaa997 100644
--- a/content/renderer/render_widget.cc
+++ b/content/renderer/render_widget.cc
@@ -33,6 +33,7 @@
 #include "content/common/content_switches_internal.h"
 #include "content/common/drag_event_source_info.h"
 #include "content/common/drag_messages.h"
+#include "content/common/frame_messages.h"
 #include "content/common/input/synthetic_gesture_packet.h"
 #include "content/common/input_messages.h"
 #include "content/common/render_message_filter.mojom.h"
@@ -615,6 +616,7 @@ bool RenderWidget::OnMessageReceived(const IPC::Message& message) {
     IPC_MESSAGE_HANDLER(InputMsg_SetFocus, OnSetFocus)
     IPC_MESSAGE_HANDLER(InputMsg_SyntheticGestureCompleted,
                         OnSyntheticGestureCompleted)
+    IPC_MESSAGE_HANDLER(FrameMsg_ShowContextMenu, OnShowContextMenu)
     IPC_MESSAGE_HANDLER(ViewMsg_Close, OnClose)
     IPC_MESSAGE_HANDLER(ViewMsg_Resize, OnResize)
     IPC_MESSAGE_HANDLER(ViewMsg_EnableDeviceEmulation,
@@ -1585,6 +1587,16 @@ void RenderWidget::SetPendingWindowRect(const WebRect& rect) {
   }
 }
 
+void RenderWidget::OnShowContextMenu(ui::MenuSourceType source_type,
+                                     const gfx::Point& location) {
+  input_handler_->set_context_menu_source_type(source_type);
+  has_host_context_menu_location_ = true;
+  host_context_menu_location_ = location;
+  if (GetWebWidget())
+    GetWebWidget()->ShowContextMenu();
+  has_host_context_menu_location_ = false;
+}
+
 void RenderWidget::OnImeSetComposition(
     const base::string16& text,
     const std::vector<WebCompositionUnderline>& underlines,