Move the closure of the subset of flang/runtime/*.h header files that
are referenced by source files outside flang/runtime (apart from unit tests)
into a new directory (flang/include/flang/Runtime) so that relative
include paths into ../runtime need not be used.
flang/runtime/pgmath.h.inc is moved to flang/include/flang/Evaluate;
it's not used by the runtime.
Differential Revision: https://reviews.llvm.org/D109107
Port external-io test to use GTest. Remove Runtime tests directory.
Rename RuntimeGTest directory to Runtime.
This is the last in a series of patches which ported tests from the old
flang/unittests/Runtime test directory to use GTest in a temporary
unittest directory under flang/unittests/RuntimeGTest. Now that all the
tests in the old directory have been ported to use GTest, the old
directory has been removed and the GTest directory has been renamed to
flang/unittests/Runtime.
Differential Revision: https://reviews.llvm.org/D105315
Reviewed by: Meinersbur, awarzynski