Fix failing TextViewTest#testTextAttr 

Set fontFamily to null overriding the value set in app theme.
Fix android.widget.cts.TextViewTest#testTextAttr

Bug: 18235143
Change-Id: I9beb2b7ee666bd4dcbc7e8239e4cdfb668114e52
diff --git a/tests/tests/widget/res/layout/textview_layout.xml b/tests/tests/widget/res/layout/textview_layout.xml
index 419bbf9..bf7f757 100644
--- a/tests/tests/widget/res/layout/textview_layout.xml
+++ b/tests/tests/widget/res/layout/textview_layout.xml
@@ -27,6 +27,7 @@
                 android:layout_height="match_parent">
 
             <TextView android:id="@+id/textview_textAttr"
+                    android:fontFamily="@null"
                     android:text="@string/text_view_hello"
                     android:textColor="@drawable/black"
                     android:textColorHighlight="@drawable/yellow"