chrome: Add ability to handle chrome menu/keyboard commands (fixes issue #3280)

This change adds a CefCommandHandler::OnChromeCommand callback for optionally
handling Chrome commands triggered via menus or keyboard shortcuts. Supported
command IDs are listed in a new cef_command_ids.h header file.

To test: Run `cefclient --enable-chrome-runtime --hide-controls`. Most commands
will blocked and removed from context menus.

libcef_dll/ctocpp/command_handler_ctocpp.h

@@ -0,0 +1,43 @@
+// Copyright (c) 2022 The Chromium Embedded Framework Authors. All rights
+// reserved. Use of this source code is governed by a BSD-style license that
+// can be found in the LICENSE file.
+//
+// ---------------------------------------------------------------------------
+//
+// This file was generated by the CEF translator tool. If making changes by
+// hand only do so within the body of existing method and function
+// implementations. See the translator.README.txt file in the tools directory
+// for more information.
+//
+// $hash=986b761d9c3bca7980b4144bb0802a9eafff9e0e$
+//
+
+#ifndef CEF_LIBCEF_DLL_CTOCPP_COMMAND_HANDLER_CTOCPP_H_
+#define CEF_LIBCEF_DLL_CTOCPP_COMMAND_HANDLER_CTOCPP_H_
+#pragma once
+
+#if !defined(BUILDING_CEF_SHARED)
+#error This file can be included DLL-side only
+#endif
+
+#include "include/capi/cef_command_handler_capi.h"
+#include "include/cef_command_handler.h"
+#include "libcef_dll/ctocpp/ctocpp_ref_counted.h"
+
+// Wrap a C structure with a C++ class.
+// This class may be instantiated and accessed DLL-side only.
+class CefCommandHandlerCToCpp
+    : public CefCToCppRefCounted<CefCommandHandlerCToCpp,
+                                 CefCommandHandler,
+                                 cef_command_handler_t> {
+ public:
+  CefCommandHandlerCToCpp();
+  virtual ~CefCommandHandlerCToCpp();
+
+  // CefCommandHandler methods.
+  bool OnChromeCommand(CefRefPtr<CefBrowser> browser,
+                       int command_id,
+                       cef_window_open_disposition_t disposition) override;
+};
+
+#endif  // CEF_LIBCEF_DLL_CTOCPP_COMMAND_HANDLER_CTOCPP_H_