android: Replace usage of deprecated Handler() constructor

src/frontends/android/app/src/main/java/org/strongswan/android/logic/CharonVpnService.java

@@ -192,7 +192,7 @@ public class CharonVpnService extends VpnService implements Runnable, VpnStateSe
 		mAppDir = getFilesDir().getAbsolutePath();
 
 		/* handler used to do changes in the main UI thread */
-		mHandler = new Handler();
+		mHandler = new Handler(getMainLooper());
 
 		mDataSource = new VpnProfileDataSource(this);
 		mDataSource.open();

src/frontends/android/app/src/main/java/org/strongswan/android/logic/VpnStateService.java

@@ -22,6 +22,7 @@ import android.os.Binder;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.IBinder;
+import android.os.Looper;
 import android.os.Message;
 import android.os.SystemClock;
 
@@ -107,7 +108,7 @@ public class VpnStateService extends Service
 	{
 		/* this handler allows us to notify listeners from the UI thread and
 		 * not from the threads that actually report any state changes */
-		mHandler = new RetryHandler(this);
+		mHandler = new RetryHandler(getMainLooper(), this);
 	}
 
 	@Override
@@ -536,8 +537,9 @@ public class VpnStateService extends Service
 	private static class RetryHandler extends Handler {
 		WeakReference<VpnStateService> mService;
 
-		public RetryHandler(VpnStateService service)
+		public RetryHandler(Looper looper, VpnStateService service)
 		{
+			super(looper);
 			mService = new WeakReference<>(service);
 		}
 

src/frontends/android/app/src/main/java/org/strongswan/android/ui/LogFragment.java

@@ -19,6 +19,7 @@ import android.content.Context;
 import android.os.Bundle;
 import android.os.FileObserver;
 import android.os.Handler;
+import android.os.Looper;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -55,7 +56,7 @@ public class LogFragment extends Fragment
 
 		mLogFilePath = getActivity().getFilesDir() + File.separator + CharonVpnService.LOG_FILE;
 
-		mLogHandler = new Handler();
+		mLogHandler = new Handler(Looper.getMainLooper());
 
 		mDirectoryObserver = new LogDirectoryObserver(getActivity().getFilesDir().getAbsolutePath());
 	}