Otherwise, all onFillRequest() calls in the same partition would use
the same flags.
Fixes: 37675138
Test: existing CtsAutoFillServiceTestCases pass
Test: CtsAssistTestCases pass
Test: PartitionedActivityTest.testAutofill4ParitionsMixManualAndAuto() pass
Change-Id: I03c8a036637bae534904d4f41265e451088cf940