inputflinger: add #includes to InterfaceMocks.h

Including InterfaceMocks.h in a test file that didn't include anything
else was causing a load of compilation errors due to these missing
includes.

Bug: 245989146
Test: check a new test file that just includes InterfaceMocks.h compiles
Change-Id: I38455b9723b83b5c61fc9abfba601e7eba5c8c7f