0b710af834
The one-at-a-time processing model was vestigial from supporting ChooserTargetService. If we need to process n shortcuts, it's inefficient to context-switch and handle n+1 messages (including the completion message) if we can instead pack all n results into a single message. The new approach is also much simpler, since we now know we have all the data on hand before proceeding - previously we forced an "unbatched" processing model on the downstream clients, and then had to design around the problems that *that* created (in particular, I haven't confirmed yet, but I *suspect* that we could get rid of the 250ms LIST_VIEW_UPDATE_MESSAGE delay after this change, since now we can just send that message a single time at the end of the batch without worrying about throttling). Further cleanup like that will come in a later CL -- for now this is the minimum change required to adopt a batch-processing model. I claim that this change is safe because there was no benefit to the one-at-a-time streaming model -- it didn't cause results to appear to the user any faster. We already had the full set of results on hand when we started emitting these messages from ChooserActivity::sendShareShortcutInfoList; the per-result processing we do in that loop isn't very expensive (and it runs in the same thread as the ChooserHandler anyways); and even if we were somehow picking up a marginal benefit, it would've been masked by the 250ms timeout. (There *maybe* could be some concern if ChooserListAdapter's addServiceResults is too expensive for us to block and call for each result in the batch, but 1. that seems unlikely; 2. if there *is* anything expensive about addServiceResults we can probably optimize it by switching to a batch-processing model in the Adapter as well; and 3. if the Adapter needs to subdivide these tasks to remain performant, it should take that responsibility on for itself.) This optimization was made possible by the removal of ChooserTargetService support (since in the old model, we actually *didn't* have all the results on hand at the start). Test: manual & atest Change-Id: Iaaab546cc274bf1879941901260b7ade62cbcaa5