[Android] fix android7 crash

[Thomas Guillem]

vlc-ports/android | branch: master | Thomas Guillem <thomas at gllm.fr> | Wed Feb 11 12:03:50 2015 +0100| [e8078cdba9efd8cca8e82df30b5d0d06faa6b557] | committer: Thomas Guillem

fix android7 crash

android7 doesn't have NewWeakGlobalRef, use a compat function for this API and
before.

> http://git.videolan.org/gitweb.cgi/vlc-ports/android.git/?a=commit;h=e8078cdba9efd8cca8e82df30b5d0d06faa6b557
---

 libvlc/jni/java_event_thread.c                |   27 +++++++++----
 libvlc/jni/java_event_thread.h                |    3 +-
 libvlc/jni/libvlcjni-vlcobject.c              |   29 +++++++++++---
 libvlc/jni/libvlcjni.c                        |   51 +++++++++++++++++++------
 libvlc/jni/utils.h                            |    3 ++
 libvlc/src/org/videolan/libvlc/VLCObject.java |   12 ++++++
 6 files changed, 99 insertions(+), 26 deletions(-)

Diff:   http://git.videolan.org/gitweb.cgi/vlc-ports/android.git/?a=commitdiff;h=e8078cdba9efd8cca8e82df30b5d0d06faa6b557