Now that we can talk to the HALs (with some out of tree CLs and
"setenforce 0"), several crashes were encountered.
Fixes here include:
- avoid hidl_handle move semantics
- check HIDL method status return value (isOk())
- convert Java short port numbers to ints
- don't pass nulls to HIDL where Strings are required
(limitations in parceling)
Test: as follows
- built
- flashed
- booted
- runtest frameworks-net passes
- "setenforce 0" and start tethering
Bug: 29337859
Bug: 32163131
Change-Id: I91314440c3a04e5f2502579b5f06dac9f25cf0cd
1185459c41