This adds a `con` argument to `execute_command` which allows you to
specify the container to execute the command on. In most cases it leaves
it as `NULL` which makes it use the focused node. We only set it when
executing `for_window` criteria such as when a view maps. This means we
don't send unnecessary IPC focus events, and fixes a crash when the
criteria command is `move scratchpad` (because we can't give focus to a
hidden scratchpad container).
Each of the shell map handlers now check to see if the view has a
workspace. It won't have a workspace if criteria has moved it to the
scratchpad.
cb66bbea42