Add back theme for overlay chips

They are inflated both as part of other UI and separately. Without
a theme the latter fails since the inflater can't find the right
color for the chip text.

Bug: 217561896
Fix: 217561896
Test: manual
Change-Id: I3b533b2ad8519eadc5e467fd34cbe8c7d993f40c

packages/SystemUI/res/layout/overlay_action_chip.xml

@@ -17,6 +17,7 @@
 <com.android.systemui.screenshot.OverlayActionChip
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:id="@+id/overlay_action_chip"
+    android:theme="@style/FloatingOverlay"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:layout_marginStart="@dimen/overlay_action_chip_margin_start"