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.cc

@@ -0,0 +1,76 @@
+// 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.
+//
+// $hash=929bc6804bc4beb1601ee44f3300a42ecc917c74$
+//
+
+#include "libcef_dll/cpptoc/command_handler_cpptoc.h"
+#include "libcef_dll/ctocpp/browser_ctocpp.h"
+#include "libcef_dll/shutdown_checker.h"
+
+namespace {
+
+// MEMBER FUNCTIONS - Body may be edited by hand.
+
+int CEF_CALLBACK
+command_handler_on_chrome_command(struct _cef_command_handler_t* self,
+                                  cef_browser_t* browser,
+                                  int command_id,
+                                  cef_window_open_disposition_t disposition) {
+  shutdown_checker::AssertNotShutdown();
+
+  // AUTO-GENERATED CONTENT - DELETE THIS COMMENT BEFORE MODIFYING
+
+  DCHECK(self);
+  if (!self)
+    return 0;
+  // Verify param: browser; type: refptr_diff
+  DCHECK(browser);
+  if (!browser)
+    return 0;
+
+  // Execute
+  bool _retval = CefCommandHandlerCppToC::Get(self)->OnChromeCommand(
+      CefBrowserCToCpp::Wrap(browser), command_id, disposition);
+
+  // Return type: bool
+  return _retval;
+}
+
+}  // namespace
+
+// CONSTRUCTOR - Do not edit by hand.
+
+CefCommandHandlerCppToC::CefCommandHandlerCppToC() {
+  GetStruct()->on_chrome_command = command_handler_on_chrome_command;
+}
+
+// DESTRUCTOR - Do not edit by hand.
+
+CefCommandHandlerCppToC::~CefCommandHandlerCppToC() {
+  shutdown_checker::AssertNotShutdown();
+}
+
+template <>
+CefRefPtr<CefCommandHandler> CefCppToCRefCounted<
+    CefCommandHandlerCppToC,
+    CefCommandHandler,
+    cef_command_handler_t>::UnwrapDerived(CefWrapperType type,
+                                          cef_command_handler_t* s) {
+  NOTREACHED() << "Unexpected class type: " << type;
+  return nullptr;
+}
+
+template <>
+CefWrapperType CefCppToCRefCounted<CefCommandHandlerCppToC,
+                                   CefCommandHandler,
+                                   cef_command_handler_t>::kWrapperType =
+    WT_COMMAND_HANDLER;