[gn build] Port 185a23e

Author: llvmgnsyncbot

llvm/utils/gn/secondary/llvm/lib/Frontend/Offloading/BUILD.gn

@@ -8,6 +8,7 @@ static_library("Offloading") {
   ]
   sources = [
     "OffloadWrapper.cpp",
+    "PropertySet.cpp",
     "Utility.cpp",
   ]
 }

llvm/utils/gn/secondary/llvm/unittests/Frontend/BUILD.gn

@@ -24,5 +24,6 @@ unittest("LLVMFrontendTests") {
     "OpenMPDirectiveNameTest.cpp",
     "OpenMPIRBuilderTest.cpp",
     "OpenMPParsingTest.cpp",
+    "PropertySetRegistryTest.cpp",
   ]
 }