Reland "Update instrumentation support for non-java debuggable runtimes"

This reverts commit 7cc22bb96e4e05cf63661eed7fd3dda5304bdacc.

Reason for revert: Relanding after a fix for jit-on-first-use failures.
The fix:
1. When shutting down jvmti agent, pause Jit threads and discard all
   JITed code.
2. Update the jit compiler options when transitioning the runtime debug
   state.

Change-Id: I076098459cc5639f9e87dae620a9297460e729e2