OpenCL vec_step feature implementation - Updated patch

Normally we test integral constant expressions in the Clang test
suite using the

int array[foo ? 1 : -1];

idiom. See for example the test/Sema/expr-comma.c test case.

Please note that test/Sema/expr-comma-c89.c contains a test for C99, whilst
test/Sema/expr-comma.c contains a test for C89.

Cheers,
Anton.

Well spotted. I renamed expr-comma-c89.c to expr-comma-c99.c in r126482.

Thanks,