Called to allow custom display of the quick menu for a windowless browser. |location| is the top left corner of the selected region. |size| is the size of the selected region. |edit_state_flags| is a combination of flags that represent the state of the quick menu. Return true (1) if the menu will be handled and execute |callback| either synchronously or asynchronously with the selected command ID. Return false (0) to cancel the menu.