[gn build] Port 868654e

Author: llvmgnsyncbot

llvm/utils/gn/secondary/llvm/lib/DWARFLinkerParallel/BUILD.gn

@@ -9,5 +9,8 @@ static_library("DWARFLinkerParallel") {
     "//llvm/lib/Object",
     "//llvm/lib/Support",
   ]
-  sources = [ "DWARFLinker.cpp" ]
+  sources = [
+    "DWARFLinker.cpp",
+    "StringPool.cpp",
+  ]
 }

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

@@ -6,5 +6,8 @@ unittest("DWARFLinkerParallelTests") {
     "//llvm/lib/Support",
     "//llvm/lib/Testing/Support",
   ]
-  sources = [ "DWARFLinkerTest.cpp" ]
+  sources = [
+    "DWARFLinkerTest.cpp",
+    "StringPoolTest.cpp",
+  ]
 }