Correctly parse RedPhone JSON.

Fixes #4182
// FREEBIE

src/org/thoughtcrime/redphone/signaling/RedPhoneAccountManager.java

@@ -1,7 +1,5 @@
 package org.thoughtcrime.redphone.signaling;
 
-import com.fasterxml.jackson.core.JsonProcessingException;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import com.squareup.okhttp.MediaType;
 import com.squareup.okhttp.OkHttpClient;
 import com.squareup.okhttp.Request;
@@ -9,6 +7,7 @@ import com.squareup.okhttp.RequestBody;
 import com.squareup.okhttp.Response;
 
 import org.thoughtcrime.securesms.util.Base64;
+import org.thoughtcrime.securesms.util.JsonUtils;
 import org.whispersystems.libaxolotl.util.guava.Optional;
 import org.whispersystems.textsecure.api.push.TrustStore;
 
@@ -52,7 +51,7 @@ public class RedPhoneAccountManager {
     builder.header("Authorization", "Basic " + Base64.encodeBytes((login + ":" + password).getBytes()));
 
     if (gcmId.isPresent()) {
-      String body = new ObjectMapper().writeValueAsString(new RedPhoneGcmId(gcmId.get()));
+      String body = JsonUtils.toJson(new RedPhoneGcmId(gcmId.get()));
       builder.put(RequestBody.create(MediaType.parse("application/json; charset=utf-8"), body));
     } else {
       builder.delete();
@@ -70,7 +69,7 @@ public class RedPhoneAccountManager {
   }
 
   public void createAccount(String verificationToken, RedPhoneAccountAttributes attributes) throws IOException {
-    String body = new ObjectMapper().writeValueAsString(attributes);
+    String body = JsonUtils.toJson(attributes);
 
     Request request = new Request.Builder()
         .url(baseUrl + "/api/v1/accounts/token/" + verificationToken)

src/org/thoughtcrime/redphone/signaling/SignalingSocket.java

@@ -30,6 +30,7 @@ import org.thoughtcrime.redphone.signaling.signals.RingingSignal;
 import org.thoughtcrime.redphone.signaling.signals.ServerSignal;
 import org.thoughtcrime.redphone.signaling.signals.Signal;
 import org.thoughtcrime.redphone.util.LineReader;
+import org.thoughtcrime.securesms.util.JsonUtils;
 import org.whispersystems.textsecure.api.push.TrustStore;
 
 import java.io.IOException;
@@ -182,7 +183,7 @@ public class SignalingSocket {
       case 404: throw new NoSuchUserException("No such redphone user.");
       case 402: throw new ServerMessageException(new String(response.getBody()));
       case 401: throw new LoginFailedException("Initiate threw 401");
-      case 200: return new ObjectMapper().readValue(response.getBody(), SessionDescriptor.class);
+      case 200: return JsonUtils.fromJson(response.getBody(), SessionDescriptor.class);
       default:  throw new SignalingException("Unknown response: " + response.getStatusCode());
       }
     } catch (IOException e) {

src/org/thoughtcrime/securesms/util/JsonUtils.java

@@ -15,6 +15,10 @@ public class JsonUtils {
     objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
   }
 
+  public static <T> T fromJson(byte[] serialized, Class<T> clazz) throws IOException {
+    return fromJson(new String(serialized), clazz);
+  }
+
   public static <T> T fromJson(String serialized, Class<T> clazz) throws IOException {
     return objectMapper.readValue(serialized, clazz);
   }