1112363 - Support incremental SWF parsing based on time budgets

Status: RESOLVED INCOMPLETE

(Firefox Graveyard :: Shumway, defect)

Description

[Till Schneidereit [:till]]

In situations where our initial SWF parsing is slower than the rate we load a file at, parsing can cause jank. To remove/reduce that, we can introduce a budget (say, 8ms) for parsing. We check that periodically and return if it's used up.

It'd be important to include zip decompression in this, and that complicates things a bit: it's conceivable that we might end up spending the entirety of the budget in decompression multiple directly consecutive times. In that case, we wouldn't be able to make any loading progress at all, which would be silly. We could get around that by only allowing budget/2 (or some other factor) for decompression, so that we're guaranteed to get some parsing done, too.