Removing some unused code from All-Apps

Bug: 229860311
Test: Verified on device
Change-Id: I72394fb421679688f87cdbf725859ec35529a59e

src/com/android/launcher3/allapps/BaseAllAppsContainerView.java

@@ -45,6 +45,7 @@ import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
 import androidx.core.graphics.ColorUtils;
 import androidx.recyclerview.widget.RecyclerView;
+import androidx.recyclerview.widget.RecyclerView.AdapterDataObserver;
 
 import com.android.launcher3.DeviceProfile;
 import com.android.launcher3.DeviceProfile.DeviceProfileListenable;
@@ -727,6 +728,12 @@ public abstract class BaseAllAppsContainerView<T extends Context & ActivityConte
                             : new BaseAdapterProvider[]{mMainAdapterProvider};
 
             adapter = getAdapter(mAppsList, adapterProviders);
+            adapter.registerAdapterDataObserver(new AdapterDataObserver() {
+                @Override
+                public void onChanged() {
+                    Log.e("Hello", "On changed", new Exception());
+                }
+            });
             mAppsList.setAdapter(adapter);
             mLayoutManager = adapter.getLayoutManager();
         }