First of all: Settings > Code Style > JavaScript > Other > Align object properties: On value
has nothing to do with variable alignment.
Second: This option (Align multiline variable declaration) is NOT available in v7 -- ONLY in upcoming v8.
EAP (Early Access Program) for PhpStorm v8 has already started and option is there. Unfortunately, it is buggy (IDE just hangs straight away when this option is activated). Issue has been fixed already .. but I cannot tell in which of next EAP builds it will be available -- just keep an eye on build number (Help | About) -- it should be 136.1141 or newer.