[PATCH] [asan] Make ASan report the correct thread address ranges to LSan.

[Kostya Serebryany]

  This is a potentially disruptive change, but I don't immediately see anything wrong.
  Today we unpoison the stack on thread death and throw. See ClearShadowForThreadStack.
  Today it includes TLS, with this change it won't.
  OTOH, we never poison TLS (do we?)

  glider, samsonov, WDYT?
  I am inclined to LGTM this.

  Or should we modify ClearShadowForThreadStack to also clear TLS's shadow?

http://llvm-reviews.chandlerc.com/D862