Fix unit test for TVRemoteProviderWatcherTest.java.

Previous submit used the wrong unit test name as a check and apparently
presubmits did not catch the bug. TVRemoteProvider package loading
is done in the constructor and the test needs to re-create the teste
object whenever changing package configuration.

Bug: 150766750
Test: atest services/tests/servicestests/src/com/android/server/tv/TvRemoteProviderWatcherTest.java
Change-Id: Ide38af5490b7d88edbb893f7a1a93c7b47beca85