Add padding around clear all button in overview.

With different languages, the length of the string "clear all" varies,
leading to the clear all button in overview looking different. This
change adds padding to account for these different lengths to
ensure that users have a consistent experience.

Screenshot for English: https://screenshot.googleplex.com/4oijo96WSfGNwWp.png
Screenshot for Ukrainian: https://screenshot.googleplex.com/Bv2963Vn96BkMeT.png

Test: Manual
Fix: 225119413
Change-Id: I09fe7bc95ca0c2fd7fe620997d1298f2670b50a4
diff --git a/quickstep/res/values/styles.xml b/quickstep/res/values/styles.xml
index 868d38b..4f0fdf1 100644
--- a/quickstep/res/values/styles.xml
+++ b/quickstep/res/values/styles.xml
@@ -152,6 +152,8 @@
         <item name="android:background">@drawable/bg_overview_clear_all_button</item>
         <item name="android:minWidth">96dp</item>
         <item name="android:minHeight">48dp</item>
+        <item name="android:paddingStart">12dp</item>
+        <item name="android:paddingEnd">12dp</item>
         <item name="android:stateListAnimator">@null</item>
     </style>