Fix (and add test for) function-like macro invocation with newlines.

Fix (and add test for) function-like macro invocation with newlines.

The test has a newline before the left parenthesis, and newlines to
separate the parentheses from the argument.

The fix involves more state in the lexer to only return a NEWLINE
token when termniating a directive. This is very similar to our
previous fix with extra lexer state to only return the SPACE token
when it would be significant for the parser.

With this change, the exact number and positioning of newlines in the
output is now different compared to "gcc -E" so we add a -B option to
diff when testing to ignore that.