diff --git a/mobile/android/base/webapp/EventListener.java b/mobile/android/base/webapp/EventListener.java
index 2312d1bd3a74..07537f21c0dc 100644
--- a/mobile/android/base/webapp/EventListener.java
+++ b/mobile/android/base/webapp/EventListener.java
@@ -5,6 +5,33 @@
 
 package org.mozilla.gecko.webapp;
 
+import org.mozilla.gecko.ActivityHandlerHelper;
+import org.mozilla.gecko.AppConstants;
+import org.mozilla.gecko.GeckoAppShell;
+import org.mozilla.gecko.GeckoEvent;
+import org.mozilla.gecko.GeckoProfile;
+import org.mozilla.gecko.favicons.decoders.FaviconDecoder;
+import org.mozilla.gecko.gfx.BitmapUtils;
+import org.mozilla.gecko.util.ActivityResultHandler;
+import org.mozilla.gecko.EventDispatcher;
+import org.mozilla.gecko.util.EventCallback;
+import org.mozilla.gecko.util.NativeEventListener;
+import org.mozilla.gecko.util.NativeJSObject;
+import org.mozilla.gecko.util.ThreadUtils;
+import org.mozilla.gecko.WebappAllocator;
+
+import android.app.Activity;
+import android.app.ActivityManager;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.PackageManager.NameNotFoundException;
+import android.graphics.Bitmap;
+import android.net.Uri;
+import android.util.Log;
+
 import java.io.File;
 import java.util.Arrays;
 import java.util.HashSet;
@@ -13,25 +40,6 @@ import java.util.Set;
 
 import org.json.JSONException;
 import org.json.JSONObject;
-import org.mozilla.gecko.ActivityHandlerHelper;
-import org.mozilla.gecko.EventDispatcher;
-import org.mozilla.gecko.GeckoAppShell;
-import org.mozilla.gecko.GeckoProfile;
-import org.mozilla.gecko.util.ActivityResultHandler;
-import org.mozilla.gecko.util.EventCallback;
-import org.mozilla.gecko.util.NativeEventListener;
-import org.mozilla.gecko.util.NativeJSObject;
-import org.mozilla.gecko.util.ThreadUtils;
-
-import android.app.Activity;
-import android.app.ActivityManager;
-import android.content.Context;
-import android.content.Intent;
-import android.content.IntentFilter;
-import android.content.pm.ApplicationInfo;
-import android.content.pm.PackageManager;
-import android.net.Uri;
-import android.util.Log;
 
 public class EventListener implements NativeEventListener  {
 
diff --git a/mobile/android/base/webapp/InstallHelper.java b/mobile/android/base/webapp/InstallHelper.java
index 8f60f5ea2d57..eda6d8b0dddd 100644
--- a/mobile/android/base/webapp/InstallHelper.java
+++ b/mobile/android/base/webapp/InstallHelper.java
@@ -19,9 +19,7 @@ import org.mozilla.gecko.GeckoAppShell;
 import org.mozilla.gecko.GeckoEvent;
 import org.mozilla.gecko.GeckoProfile;
 import org.mozilla.gecko.gfx.BitmapUtils;
-import org.mozilla.gecko.util.EventCallback;
-import org.mozilla.gecko.util.NativeEventListener;
-import org.mozilla.gecko.util.NativeJSObject;
+import org.mozilla.gecko.util.GeckoEventListener;
 import org.mozilla.gecko.util.ThreadUtils;
 
 import android.content.Context;
@@ -29,7 +27,7 @@ import android.graphics.Bitmap;
 import android.net.Uri;
 import android.util.Log;
 
-public class InstallHelper implements NativeEventListener {
+public class InstallHelper implements GeckoEventListener {
     private static final String LOGTAG = "GeckoWebappInstallHelper";
     private static final String[] INSTALL_EVENT_NAMES = new String[] {"Webapps:Postinstall"};
     private final Context mContext;
@@ -38,7 +36,7 @@ public class InstallHelper implements NativeEventListener {
 
     public static interface InstallCallback {
         // on the GeckoThread
-        void installCompleted(InstallHelper installHelper, String event, NativeJSObject message);
+        void installCompleted(InstallHelper installHelper, String event, JSONObject message);
 
         // on the GeckoBackgroundThread
         void installErrored(InstallHelper installHelper, Exception exception);
@@ -164,7 +162,7 @@ public class InstallHelper implements NativeEventListener {
     }
 
     @Override
-    public void handleMessage(String event, NativeJSObject message, EventCallback callback) {
+    public void handleMessage(String event, JSONObject message) {
         EventDispatcher.getInstance().unregisterGeckoThreadListener(this, INSTALL_EVENT_NAMES);
 
         if (mCallback != null) {
diff --git a/mobile/android/base/webapp/WebappImpl.java b/mobile/android/base/webapp/WebappImpl.java
index 7dceb19d9408..5adc670b59f1 100644
--- a/mobile/android/base/webapp/WebappImpl.java
+++ b/mobile/android/base/webapp/WebappImpl.java
@@ -18,7 +18,6 @@ import org.mozilla.gecko.GeckoThread;
 import org.mozilla.gecko.R;
 import org.mozilla.gecko.Tab;
 import org.mozilla.gecko.Tabs;
-import org.mozilla.gecko.util.NativeJSObject;
 import org.mozilla.gecko.webapp.InstallHelper.InstallCallback;
 
 import android.content.Intent;
@@ -326,13 +325,13 @@ public class WebappImpl extends GeckoApp implements InstallCallback {
     }
 
     @Override
-    public void installCompleted(InstallHelper installHelper, String event, NativeJSObject message) {
+    public void installCompleted(InstallHelper installHelper, String event, JSONObject message) {
         if (event == null) {
             return;
         }
 
         if (event.equals("Webapps:Postinstall")) {
-            String origin = message.optString("origin", null);
+            String origin = message.optString("origin");
             launchWebapp(origin);
         }
     }