Hide "Inspect Element" context menu item from <webview> when <webview>

components/renderer_context_menu/context_menu_content_type.h

Index: components/renderer_context_menu/context_menu_content_type.h
diff --git a/components/renderer_context_menu/context_menu_content_type.h b/components/renderer_context_menu/context_menu_content_type.h
index 81003dd5b17a0c8f0a213271e980388cafe279e9..c1e6a74f375c9ccdd7a5a7c914c29607a0e905b9 100644
--- a/components/renderer_context_menu/context_menu_content_type.h
+++ b/components/renderer_context_menu/context_menu_content_type.h
@@ -70,6 +70,10 @@ class ContextMenuContentType {
 
   const extensions::Extension* GetExtension() const;
 
+  const content::WebContents* source_web_contents() const {
+    return source_web_contents_;
+  }
+
  private:
   bool SupportsGroupInternal(int group);