Affirmative names for argument parsing namespace destinations.

[Rostepher]

Purpose

The main goal for this PR is to rename all argument-parsing namespace destinations of the form skip_build_* and skip_test_* to a more consistent and affirmative build_* and test_* respectively. It also corrects the discrepancy between build_*_device and test_*_host, now all the test variables will be test_*_device as well. The actual argument option strings have not been changed in anyway, these renames are all under-the-hood so to speak.

This PR should be the last step necessary to pave the way for #11827.

rdar://34336890

[Rostepher]

@swift-ci please smoke test

[gottesmm]

This looks reasonable to me. Can you add some documentation where I asked below on those two classes?

[gottesmm]

Can you add documentation for this and the other option?

[Rostepher]

Sure thing! I don't expect these classes and really this entire module to hang around for very long, I just needed this particular behavior sooner than later.

[Rostepher]

@swift-ci please smoke test

[davezarzycki]

This broke my "fast debug build" setup. Ninja now fails to start with the following error: '/Volumes/data/wt/swift/master/swift/tools/SwiftSyntax/swiftFoundation-swiftmodule-macosx-x86_64', needed by 'tools/SwiftSyntax/macosx/x86_64/SwiftSyntax.o', missing and no known rule to make it

My build script:

#!/bin/sh

time nice ./utils/build-script \
	--build-subdir="$(dirname $PWD)/d" \
	--llvm-targets-to-build X86 \
	--skip-ios --skip-tvos --skip-watchos \
	--skip-build-benchmarks true \
	--build-swift-static-stdlib false \
	--build-swift-static-sdk-overlay false \
	--build-swift-dynamic-sdk-overlay false \
	--build-swift-stdlib-unittest-extra false \
	-r \
	--debug-swift \
	--debug-swift-stdlib \
	"$@"

[davezarzycki]

I've filed a bug: https://bugs.swift.org/browse/SR-5911