Allow sanitize attribute on cc_objects and propagate sanitize attributes into them.

Without this change, we can end up failing to sanitize parts of libraries
that are compiled as cc_objects, such as bcm_object.o in boringssl. This
is normally harmless (except that the sanitizer would fail to detect bugs
in unsanitized code), however boringssl in particular needs to be compiled
with HWASAN enabled in all translation units in order to avoid link errors
with newer toolchains that support HWASAN global instrumentation.

Change-Id: Ib8bd325f76b7852cab435bff79d6945768298a5c