[gki]  Use new jsoncpp API am: d1c4c4b290

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Gki/+/1608354

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I702dc8a28a167de6c6815daa5272a77823e1a606
diff --git a/build_gki_apex_manifest.cpp b/build_gki_apex_manifest.cpp
index 796f1ad..016c216 100644
--- a/build_gki_apex_manifest.cpp
+++ b/build_gki_apex_manifest.cpp
@@ -46,7 +46,8 @@
   root["name"] = apex_name;
   root["version"] = apex_version;
   root["preInstallHook"] = "bin/com.android.gki.preinstall";
-  std::string json_string = Json::StyledWriter().write(root);
+  Json::StreamWriterBuilder factory;
+  std::string json_string = Json::writeString(factory, root);
   if (!android::base::WriteStringToFile(json_string, out_file)) {
     PLOG(ERROR) << "Cannot write to " << out_file;
     return EX_SOFTWARE;