Remove #handleWtfs from PluginInitializer.

This method was empty anyways.

Bug: 194781951
Test: manual
Change-Id: I404704090dc360e05b1db04815d394d47d63af28

quickstep/src/com/android/launcher3/uioverrides/plugins/PluginInitializerImpl.java

@@ -18,10 +18,6 @@ import com.android.launcher3.Utilities;
 import com.android.systemui.shared.plugins.PluginInitializer;
 
 public class PluginInitializerImpl implements PluginInitializer {
-    @Override
-    public void handleWtfs() {
-    }
-
     public boolean isDebuggable() {
         return Utilities.IS_DEBUG_DEVICE;
     }