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.

tests/cefclient/browser/client_handler_osr.h

@@ -77,6 +77,7 @@ class ClientHandlerOsr : public ClientHandler,
 
   ClientHandlerOsr(Delegate* delegate,
                    OsrDelegate* osr_delegate,
+                   bool with_controls,
                    const std::string& startup_url);
 
   // This object may outlive the OsrDelegate object so it's necessary for the