Move Process_PointerCapture to CursorInputMapper_test

This test will now be using the new test infra set up in
CursorInputMapper_test instead of the one in InputReader_test.

This specific test documents the behaviour of pointer capture - the
generation of ACTION_MOVE events during pointer capture, and the use of
SOURCE_MOUSE_RELATIVE.

Bug: 283812079
Test: atest inputflinger_tests
Change-Id: I87d707dfd418ab7d6203571a4acf7a090d247304