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/cpptoc/command_handler_cpptoc.h

@@ -0,0 +1,38 @@
+// 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.
+//
+// $hash=85e5de7b82a22ab4738de3a6a2bb141eb5c79579$
+//
+
+#ifndef CEF_LIBCEF_DLL_CPPTOC_COMMAND_HANDLER_CPPTOC_H_
+#define CEF_LIBCEF_DLL_CPPTOC_COMMAND_HANDLER_CPPTOC_H_
+#pragma once
+
+#if !defined(WRAPPING_CEF_SHARED)
+#error This file can be included wrapper-side only
+#endif
+
+#include "include/capi/cef_command_handler_capi.h"
+#include "include/cef_command_handler.h"
+#include "libcef_dll/cpptoc/cpptoc_ref_counted.h"
+
+// Wrap a C++ class with a C structure.
+// This class may be instantiated and accessed wrapper-side only.
+class CefCommandHandlerCppToC
+    : public CefCppToCRefCounted<CefCommandHandlerCppToC,
+                                 CefCommandHandler,
+                                 cef_command_handler_t> {
+ public:
+  CefCommandHandlerCppToC();
+  virtual ~CefCommandHandlerCppToC();
+};
+
+#endif  // CEF_LIBCEF_DLL_CPPTOC_COMMAND_HANDLER_CPPTOC_H_