Refactor interceptKeyBeforeQueueing tests in FakeInputDispatcherPolicy

Refactor to explicitly set the `delay` of an intercept result, which
allows granular return values.

Bug: 384113980
Test: atest InputDispatcherTest

Flag: TEST_ONLY

Change-Id: I8c581780bc5fbac96fc00ac2750e5d015dbcc9f0
3 files changed