This patch fixes two related issues.
1. The AutoStopwatch uses a stack-allocated `mozilla::Vector` to
communicate with its callback during each compartment switch.
This vector was designed to allow its contents to be stack-allocated
but they turned out to be accidentally heap-allocated.
2. During each tick, the stopwatch fills a vector `recentGroups_`.
This vector always started with minimal capacity and had to grow
repeatedly as groups were added, causing repeated reallocations.
This patch preallocates `recentGroups_` to have the same capacity as the
previous tick. We expect that this should eventually reach a stable size
that closely matches the actual needs of the process.
Bug 1342553 - Part 0.1: Use try-catch for IteratorClose in for-of
Bug 1343072 - Update HasLiveStackValueAtDepth to follow the change in
JSTRY_FOR_OF
Bug 1344753 - Update for-of stack depth in
ControlFlowGenerator::processWhileOrForInLoop
Issue #74
