Frameworks: Silently ignore InterruptedException

Apps seem to rely on this undocumented behavior so that the
threaded sync adapter doesn't crash an app. That's really
bad on the app side, but we will have to live with it.

Bug: 67986472
Bug: 70122540
Test: m
Test: Device boots
Test: m cts && cts-tradefed run commandAndExit cts-dev --module CtsContentTestCases -c android.content.cts.SharedPreferencesTest
Change-Id: I1ee4dfba4ad29c4f66fa60d3c8f8a99900b3447a