Fix postconditions by saving FrameState at terminal instructions

Summary: We didn't always have a state snapshot for the terminal
block, so attempts to grab postconditions from a FrameState snapshot
weren't guaranteed to work.  Let's always save them instead.

Reviewed By: @ottoni

Differential Revision: D1283781
Fix hhprof decoding of SrcKey "addresses"

Summary: Fix issue with treating unsigned "addresses" (which are really
SrcKeys) as signed and then converting them later.

Reviewed By: @jano

Differential Revision: D1285004
Handle loops in computeLiveRegs

Summary: Iterate until stable.  This adds one extra iteration for
non-loop code, but it's a quick pass anyway.  If perflab
complains we can do something more elaborate.

Reviewed By: @swtaarrs

Differential Revision: D1282587
Fix undefined variable

Summary: thats it

Reviewed By: @asukhachev

Differential Revision: D1285815
Fix typo in CURLFile.php

Summary: thats it

Reviewed By: @fredemmott

Differential Revision: D1285733