Better compiler warning tests

Better compiler warning tests

These changes allow all bytecomp-tests to be run interactively.

* test/lisp/emacs-lisp/bytecomp-tests.el (bytecomp--with-warning-test)
(bytecomp--define-warning-file-test): Interpret any space in the
pattern as arbitrary whitespace to tolerate line breaks.
Don't abuse the expected-failure mechanism when checking
for the expected absense of a warning.
(bytecomp/*.el): Rewrite patterns to work with line breaks
in the middle.