Bug 850523 (part 2) - Use C++ comments in LifoAlloc.{cpp,h}.  r=wmccloskey.

--HG--
extra : rebase_source : 395321642042559ef2484445fa13c03ba22e8390
Bug 807241 Use ITfMessagePump and ITfKeystrokeMgr r=jimm
Bug 850000 - Don't clobber exceptions set in security wrapper check() hooks. r=mrbkap
Bug 813901 - Tests. r=mrbkap