supporting swipable home screens on xlarge devices

- icons and widgets on home screens can be "dimmed"
- celllayout no longer renders a dimmed version of itself, but instead its children make dimmed versions of themselves
- celllayout no longer always takes up full size of workspace, in landscape mode 
neighboring screens (celllayouts) are visible
- on xlarge devices, in landscape mode side screens are "dimmed"
- moved holographic outline helper to its own file
- fixed bug where mini-screens were still able to scroll left/right

Change-Id: I9e85ab4147edfae1e7525c3d11d42be3fabf4f6d
diff --git a/src/com/android/launcher2/LauncherAppWidgetHost.java b/src/com/android/launcher2/LauncherAppWidgetHost.java
index a5761ec..75a9940 100644
--- a/src/com/android/launcher2/LauncherAppWidgetHost.java
+++ b/src/com/android/launcher2/LauncherAppWidgetHost.java
@@ -34,6 +34,10 @@
     @Override
     protected AppWidgetHostView onCreateView(Context context, int appWidgetId,
             AppWidgetProviderInfo appWidget) {
-        return new LauncherAppWidgetHostView(context);
+        if (LauncherApplication.isScreenXLarge()) {
+            return new DimmableAppWidgetHostView(context);
+        } else {
+            return new AppWidgetHostView(context);
+        }
     }
 }