Update vertical drag handle (all apps arrow)

- Change drawable to match specs, using ShadowDrawable to
  add shadow when necessary based on workspace theme.
- New drawable is 18dp by 6dp; add support for different
  width vs height, and decouple from workspace page
  indicator (which is still 24dp tall).

Bug: 151768994
Change-Id: Icfd0eac197ebc4d1f5bb799f8538c4bd99d800cd
diff --git a/res/layout/launcher.xml b/res/layout/launcher.xml
index ab6c960..de13277 100644
--- a/res/layout/launcher.xml
+++ b/res/layout/launcher.xml
@@ -57,7 +57,7 @@
         <com.android.launcher3.pageindicators.WorkspacePageIndicator
             android:id="@+id/page_indicator"
             android:layout_width="match_parent"
-            android:layout_height="@dimen/vertical_drag_handle_size"
+            android:layout_height="@dimen/workspace_page_indicator_height"
             android:layout_gravity="bottom|center_horizontal"
             android:theme="@style/HomeScreenElementTheme" />