Bug 995803 - fix crash in java.lang.IllegalStateException: Already registered Webapps. r=mfinkle

mobile/android/base/GeckoApp.java

@@ -213,6 +213,7 @@ public abstract class GeckoApp
     private int mSignalStrenth;
     private PhoneStateListener mPhoneStateListener = null;
     private boolean mShouldReportGeoData;
+    private EventListener mWebappEventListener;
 
     abstract public int getLayout();
     abstract public boolean hasTabsSideBar();
@@ -1547,7 +1548,11 @@ public abstract class GeckoApp
             "Update:Download",
             "Update:Install");
 
-        EventListener.registerEvents();
+        if (mWebappEventListener == null) {
+            mWebappEventListener = new EventListener();
+            mWebappEventListener.registerEvents();
+        }
+
 
         if (SmsManager.getInstance() != null) {
           SmsManager.getInstance().start();
@@ -2081,7 +2086,10 @@ public abstract class GeckoApp
             "Update:Download",
             "Update:Install");
 
-        EventListener.unregisterEvents();
+        if (mWebappEventListener != null) {
+            mWebappEventListener.unregisterEvents();
+            mWebappEventListener = null;
+        }
 
         deleteTempFiles();
 

mobile/android/base/webapp/EventListener.java

@@ -42,20 +42,8 @@ public class EventListener implements GeckoEventListener {
 
     private static final String LOGTAG = "GeckoWebappEventListener";
 
-    private EventListener() { }
-
-    private static EventListener mEventListener;
-
-    private static EventListener getEventListener() {
-        if (mEventListener == null) {
-            mEventListener = new EventListener();
-        }
-        return mEventListener;
-    }
-
-    public static void registerEvents() {
-        EventDispatcher.getInstance().registerGeckoThreadListener(
-            EventListener.getEventListener(),
+    public void registerEvents() {
+        EventDispatcher.getInstance().registerGeckoThreadListener(this,
             "Webapps:Preinstall",
             "Webapps:InstallApk",
             "Webapps:Postinstall",
@@ -64,9 +52,8 @@ public class EventListener implements GeckoEventListener {
             "Webapps:GetApkVersions");
     }
 
-    public static void unregisterEvents() {
-        EventDispatcher.getInstance().unregisterGeckoThreadListener(
-            EventListener.getEventListener(),
+    public void unregisterEvents() {
+        EventDispatcher.getInstance().unregisterGeckoThreadListener(this,
             "Webapps:Preinstall",
             "Webapps:InstallApk",
             "Webapps:Postinstall",