As much as Gmail shines when it's on the web, some of its most avid users stay in native apps for the multitasking; having to check a past message in the web client has usually meant putting the current draft on hold, or at least maintaining a near-photographic memory. Google wants to translate some of that desktop experience to the web through a new composition interface it's testing as of today. New messages start off in a shrinkable pop-up that lets us find old threads without having to put the new conversation on ice, even we're indecisive enough to leave multiple unfinished e-mail messages op