Set compile_dex explicitly for FakeApexSystemServices

java_library modules don't compile to dex by default, but dex files
are needed to install on the device, either directly or via an apex.
Soong was implicilty adding compile_dex to java_library modules that
were in apexes, but this requires propagating information down from
apex modules in a way that prevents incremental analysis.  Set it
explicitly instead.

Bug: 372543712
Test: no change to build.ninja
Change-Id: Ie97f6b2a76426955b91b2ed010d40ac73ce081be