Fix JVMTI GetStackTrace bug

GetStackTrace would incorrectly return ERR(ILLEGAL_ARGUMENT) if the
number frames returned was less then the start depth and start depth
was >= 0. This made some legal stack trace calls impossible.

Instead it should have been checking that at least one frame was
retrieved (since otherwise the start-depth was off the stack).

Test: ./test.py --host
Bug: 132196976
Change-Id: I9f959569f90dbb75de0010173b119472a4b5864e
Merged-In: I9f959569f90dbb75de0010173b119472a4b5864e
(cherry picked from commit 342b69492cd0789d1c0903bb6d948e505e708048)