Clear the scan list when an empty list is received

When the framework receives an empty scan list from supplicant, it does
not clear the local list. So the UI will continue to show the previous
scan list even when there are no APs around. So clear the local list,
when an empty list is received.

CRs-Fixed: 552212
Change-Id: I8715bc31ce0df7bd54c96fcf7d7b73592429f12a
Fix a JNI local reference leak in MediaDrm

A reference leak was found in the subtitle usecase that also
applies to android_media_MediaDrm.cpp
(Code taken from the similar fix in android_media_MediaPlayer.cpp)

Change-Id: Icc4b25e4adc9a600ff4ac99a7a8478bb55a6e348
Re-initialize error after attach

If flag for error after attach is not reinitialized, it may cause
NullPointerException on subsequent onAttachedWindow if error text
was reset to null.

Change-Id: I8976c28a6ca71017e5c4b3f29d4eeeb2eda48c38
Merge "Re-initialize error after attach" into kitkat
Merge "Fix a JNI local reference leak in MediaDrm" into kitkat
Merge "Clear the scan list when an empty list is received" into kitkat