Fix JNI usage issues in Android TestLogParser

Fix JNI usage issues in Android TestLogParser

 * Android TestLogParser used CallObjectMethod() on Java methods returning
void, which causes CheckJNI to throw an error. Changed to use correct
CallVoidMethod().

 * TestLogListener wrapper was not freeing local jstring references,
which given large parse buffer size could easily lead to ART local
reference table overflow. Fixed by freeing all local references as soon
as the objects are passed to the Java / VM side.

Change-Id: I19811be6fdc0f3d77bc7a0d99d243529031d3b08