Fix memory leak in ApnSettings-activity

When destroying the activity, the HandlerThread isnt stopped. This
results in that the thread remains, and if you enter/exit the
activity multiple times, you will end up with multiple threads and
a small memory leak

Change-Id: I4779d2625e6002b55066dd034c84d743b9f80ef5

src/com/android/settings/ApnSettings.java

@@ -81,6 +81,7 @@ public class ApnSettings extends PreferenceActivity implements
 
     private RestoreApnUiHandler mRestoreApnUiHandler;
     private RestoreApnProcessHandler mRestoreApnProcessHandler;
+    private HandlerThread mRestoreDefaultApnThread;
 
     private String mSelectedKey;
 
@@ -141,10 +142,19 @@ public class ApnSettings extends PreferenceActivity implements
     @Override
     protected void onPause() {
         super.onPause();
-        
+
         unregisterReceiver(mMobileStateReceiver);
     }
 
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+
+        if (mRestoreDefaultApnThread != null) {
+            mRestoreDefaultApnThread.quit();
+        }
+    }
+
     private void fillList() {
         String where = "numeric=\""
             + android.os.SystemProperties.get(TelephonyProperties.PROPERTY_ICC_OPERATOR_NUMERIC, "")
@@ -273,12 +283,13 @@ public class ApnSettings extends PreferenceActivity implements
             mRestoreApnUiHandler = new RestoreApnUiHandler();
         }
 
-        if (mRestoreApnProcessHandler == null) {
-            HandlerThread restoreDefaultApnThread = new HandlerThread(
+        if (mRestoreApnProcessHandler == null ||
+            mRestoreDefaultApnThread == null) {
+            mRestoreDefaultApnThread = new HandlerThread(
                     "Restore default APN Handler: Process Thread");
-            restoreDefaultApnThread.start();
+            mRestoreDefaultApnThread.start();
             mRestoreApnProcessHandler = new RestoreApnProcessHandler(
-                    restoreDefaultApnThread.getLooper(), mRestoreApnUiHandler);
+                    mRestoreDefaultApnThread.getLooper(), mRestoreApnUiHandler);
         }
 
         mRestoreApnProcessHandler