MediaRecorderClient: Fix binder dereference while connecting to camera

IServiceManager.getService can return NULL. Check for NULL and
return NO_INIT on failure.

Bug: 34870127
Test: adb shell am instrument -e size small -w 'android.media.cts/android.support.test.runner.AndroidJUnitRunner'
Change-Id: I6d71f8c0e89a556e64f5250ba1ab742e485f1ebc