Reading window_animation_scale from Settings.Global

It moved from Settings.System, so there were constant warnings in the
logs. This only affects dogfood builds.

Change-Id: Ic3c179837f78a8040579fcc6ad485f6fabe1c2a1
diff --git a/src/com/android/launcher3/PagedView.java b/src/com/android/launcher3/PagedView.java
index 394b950..36b9e97 100644
--- a/src/com/android/launcher3/PagedView.java
+++ b/src/com/android/launcher3/PagedView.java
@@ -1404,8 +1404,8 @@
         }
 
         if (FeatureFlags.IS_DOGFOOD_BUILD) {
-            duration *= Settings.System.getFloat(getContext().getContentResolver(),
-                    Settings.System.WINDOW_ANIMATION_SCALE, 1);
+            duration *= Settings.Global.getFloat(getContext().getContentResolver(),
+                    Settings.Global.WINDOW_ANIMATION_SCALE, 1);
         }
 
         whichPage = validateNewPage(whichPage);