Revert "Revert "Provide AllApps item OnLongClickListener through ActivityContext.""

This reverts commit 853a5b9e0c.

Fixes SecondaryDisplayLauncher class by using lambda instead of method
reference for #getAllAppsItemLongClickListener. This change is necessary
because mDragLayer is late-init.

Test: Home Settings > Developer Options > Launch Secondary Display
Bug: 289261756
Flag: No
Change-Id: I7b83f81651dde360edea6ee7bea6cc82441e6bef

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

@@ -892,15 +892,6 @@ public class ActivityAllAppsContainerView<T extends Context & ActivityContext>
         container.put(R.id.work_tab_state_id, state);
     }
 
-    /**
-     * Sets the long click listener for icons
-     */
-    public void setOnIconLongClickListener(OnLongClickListener listener) {
-        for (AdapterHolder holder : mAH) {
-            holder.mAdapter.setOnIconLongClickListener(listener);
-        }
-    }
-
     public AllAppsStore getAppsStore() {
         return mAllAppsStore;
     }