* Treat SSL NOT_HANDSHAKING as FINISHED.

The code comment states that NOT_HANDSHAKING should be treated as FINISHED, but fails to reset the ```initialHandshake``` flag.

On Android, client connections complete OK in the NOT_HANDSHAKING state.  This may be a bug on Android, but it has not changed since Android 2.3, and current source suggests it will stay that way ( https://android.googlesource.com/platform/libcore/+/master/luni/src/test/java/libcore/javax/net/ssl/SSLEngineTest.java )

The fix is to treat NOT_HANDSHAKING as FINISHED as per code comment.  Tests run fine on OS X and travis as far as I can see.