[Tests] Fix round-trip test to build with target libraries.

The round-trip test was relying on a host library, but that only works where
we aren't cross-compiling.  Using a target library instead was a little more
complicated than it looked because libswiftDemangling doesn't get built for
the target.  However, it *is* part of the other Swift libraries on the host,
but there's an extra namespace shoehorned in.

Author: al45tair

test/TypeRoundTrip/Inputs/RoundTrip/RoundTrip.cpp

@@ -12,12 +12,12 @@ using namespace swift;
 
 static std::string nameForMetadata(const Metadata *md)
 {
-  Demangle::StackAllocatedDemangler<1024> dem;
+  Demangle::__runtime::StackAllocatedDemangler<1024> dem;
   auto nodeTree = _swift_buildDemanglingForMetadata(md, dem);
   if (!nodeTree)
     return "<unknown>";
 
-  std::string result = Demangle::nodeToString(nodeTree);
+  std::string result = Demangle::__runtime::nodeToString(nodeTree);
   return result;
 }
 
@@ -26,11 +26,11 @@ extern "C" SWIFT_CC(swift) void roundTripType(const Metadata *md) {
   const std::string mdName = ::nameForMetadata(md);
 
   // Convert it to a Node tree
-  Demangle::StackAllocatedDemangler<1024> dem;
+  Demangle::__runtime::StackAllocatedDemangler<1024> dem;
   auto nodeTree = _swift_buildDemanglingForMetadata(md, dem);
 
   // Mangle that
-  std::string mangledName = Demangle::mangleNode(nodeTree);
+  std::string mangledName = Demangle::__runtime::mangleNode(nodeTree);
 
   // Look up the result
   auto result = swift_getTypeByMangledName(MetadataState::Abstract,

test/TypeRoundTrip/round-trip.swift

@@ -1,12 +1,12 @@
 // RUN: %empty-directory(%t)
-// RUN: %target-clang -std=c++14 %target-rtti-opt %target-pic-opt %target-msvc-runtime-opt -g -c %S/Inputs/RoundTrip/RoundTrip.cpp -I%swift_obj_root/include -I%swift_src_root/include -I%swift_src_root/stdlib/include -I%swift_src_root/stdlib/public/runtime -I%llvm_src_root/include -I%llvm_obj_root/include -o %t/RoundTrip.o
+// RUN: %target-clang -std=c++14 %target-rtti-opt %target-pic-opt %target-msvc-runtime-opt -DSWIFT_INLINE_NAMESPACE=__runtime -g -c %S/Inputs/RoundTrip/RoundTrip.cpp -I%swift_obj_root/include -I%swift_src_root/include -I%swift_src_root/stdlib/include -I%swift_src_root/stdlib/public/runtime -I%llvm_src_root/include -I%llvm_obj_root/include -o %t/RoundTrip.o
 // RUN: %target-build-swift -g -static -emit-module-path %t/RoundTrip.swiftmodule -emit-module -emit-library -module-name RoundTrip -o %t/%target-static-library-name(RoundTrip) %S/Inputs/RoundTrip/RoundTrip.swift %t/RoundTrip.o
 // RUN: echo "// AUTOGENERATED" > %t/all-tests.swift
 // RUN: for module in %S/Inputs/testcases/*.swift; do modname=$(basename $module .swift); echo "import $modname" >> %t/all-tests.swift; done
 // RUN: echo "func runAllTests() throws {" >> %t/all-tests.swift
 // RUN: for module in %S/Inputs/testcases/*.swift; do modname=$(basename $module .swift); %target-build-swift -g -static -emit-module-path %t/$modname.swiftmodule -emit-module -emit-library -module-name $modname -o %t/%target-static-library-name($modname) -I%t -L%t $module -lRoundTrip; echo "  print(\"--- $modname\")" >> %t/all-tests.swift; echo "  $modname.test()" >> %t/all-tests.swift; echo "  print(\"\")" >> %t/all-tests.swift; echo "-l$modname" >> %t/link.txt; done
 // RUN: echo "}" >> %t/all-tests.swift
-// RUN: %target-build-swift -g -I%t -o %t/round-trip %s %t/all-tests.swift -L%t -L%swift_obj_root/lib -L%swift_obj_root/lib/swift %target-cxx-lib $(cat %t/link.txt) -lRoundTrip -lswiftDemangling -lswiftReflection
+// RUN: %target-build-swift -g -I%t -o %t/round-trip %s %t/all-tests.swift -L%t %target-cxx-lib $(cat %t/link.txt) -lRoundTrip -lswiftReflection
 // RUN: %target-codesign %t/round-trip
 // RUN: %target-run %t/round-trip | %FileCheck %s