Summary:
A previous change made pulse look into value histories for causes of
invalidation in case the access trace of a value already contained the
reason why that value is invalid, in order to save printing the
invalidation trace in addition to the access trace. It also made
reporting more accurate for null dereference as the source of null was
often better identified (in cases where several values are null or
zero).
But, the history is also relevant to the bug type and the error message.
Make these take histories into account too.
Also fix a bug where we didn't look inside the sub-histories contained
within function calls when looking for an invalidation along the
history.
Reviewed By: da319
Differential Revision: D28254334
fbshipit-source-id: 5ca00ee54