* test-suite/tests/coverage.test ("instrumented-source-files"): Adapt to
new expectation that all files loaded on the system will be present in
the source information.
* test-suite/tests/coverage.test ("procedure-execution-count"): Adapt
test to new behavior of procedure-execution-count of an unseen
procedure: zero, not false.
* test-suite/tests/coverage.test ("line-execution-counts"): Fix test for
even/odd? in letrec. The test profiles the execution of even?, not
the letrec, so the last line is in fact not reached.
* test-suite/tests/coverage.test ("procedure-execution-count")["called
from C"]: Throw 'unresolved when `scm_call_2' cannot be resolved.
Reported by Eli Zaretskii <eliz@gnu.org>.
* module/system/vm/coverage.scm (with-code-coverage): Switch current
thread to VM, using `set-thread-vm!'.
* test-suite/tests/coverage.test ("procedure-execution-count")["called
from C"]: New test.
