Split logtags implementations for cc and java

Logtags files in cc and java are treated fundamentally differently.
In cc, they are not used for compiling at all, but need to be passed
to Make to be combined into the global logtags list, and logtag files
are listed in a logtags property.  In java they are listed in srcs
and produce generated code that is compiled in, and so shouldn't
also need to be listed in a logtags property.

Move the logtags property to cc and export it to Make from there,
and have java extract logtags files from srcs to be exported to
Make.

Test: m checkbuild
Change-Id: I31d49289efe72db60d2f33566df771b4a3ebc8a0