GenericSource: reset mDrmManagerClient when mDataSource is cleared. am: 224858e719 am: 69c8e36da7 am: 3fcddfd23a am: e01ba47052
am: adadada4f0

* commit 'adadada4f00eaf44bbc616be7a7d30010750560e':
  GenericSource: reset mDrmManagerClient when mDataSource is cleared.