Remove hardware layers. Replace alpha by colors-with-alpha

Bug:5097580

Change-Id: Icd1815d78cd482f6fa62663aa9283ff743e40642
diff --git a/res/layout/call_detail.xml b/res/layout/call_detail.xml
index 83d3e20..8356aa8 100644
--- a/res/layout/call_detail.xml
+++ b/res/layout/call_detail.xml
@@ -67,7 +67,7 @@
     <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="@dimen/call_detail_contact_background_overlay_height"
-        android:background="#3F000000"
+        android:background="#7F000000"
         android:layout_alignParentLeft="true"
         android:layout_alignBottom="@id/contact_background_sizer"
     />