[TextField] Link OnItemSelectedListener of AutoCompleteTextView with the actual drop-down list

Framework has no default implementation of how or when OnItemSelectedListener will be called. We need to link it with the actual ListPopupWindow we are going to show.

Resolves #1804

PiperOrigin-RevId: 449725174

Author: drchen

lib/java/com/google/android/material/textfield/MaterialAutoCompleteTextView.java

@@ -41,6 +41,7 @@
 import android.view.accessibility.AccessibilityManager;
 import android.widget.AdapterView;
 import android.widget.AdapterView.OnItemClickListener;
+import android.widget.AdapterView.OnItemSelectedListener;
 import android.widget.ArrayAdapter;
 import android.widget.Filterable;
 import android.widget.ListAdapter;
@@ -192,6 +193,12 @@ public void setRawInputType(int type) {
     onInputTypeChanged();
   }
 
+  @Override
+  public void setOnItemSelectedListener(@Nullable OnItemSelectedListener listener) {
+    super.setOnItemSelectedListener(listener);
+    modalListPopup.setOnItemSelectedListener(getOnItemSelectedListener());
+  }
+
   /**
    * Sets the simple string items of auto-completion with the given string array resource. This
    * method will create a default {@link ArrayAdapter} with a default item layout specified by