Fix handling of hijacked events in synchronous mode

Summary:
This patch includes the following changes:
* Fix Target::Launch to handle hijacked event in synchronous mode
* Improve MiStartupOptionsTestCase tests to expect *stopped (MI)
* Add SBProcess::GetStopEventForStopID
* Add ProcessModID::SetStopEventForLastNaturalStopID/GetStopEventForStopID
* Add const qualifier to ProcessModID::GetLastNaturalStopID
* Add SBProcess::GetStopEventForStopID
* Don't broadcast hijacked event in Target::Launch
* Add CMICmnLLDBDebugger::CheckIfNeedToRebroadcastStopEvent/RebroadcastStopEvent

Test Plan: ./dotest.py -v --executable $BUILDDIR/bin/lldb tools/lldb-mi/startup_options/

Reviewers: zturner, jingham, clayborg, abidh

Reviewed By: clayborg

Subscribers: abidh, zturner, lldb-commits, clayborg, jingham

Differential Revision: http://reviews.llvm.org/D9371

llvm-svn: 237781