Minor refactoring prior to major refactoring.

Removal of blur layer.
Deferral of Surface actions in BlackFrame from ctor to first use.
Combine common test into single method okToDisplay().
Remove redundant logic in DimAnimator.

Change-Id: I43af0415794a8f142803ce94d7e17539aafac67d
diff --git a/services/java/com/android/server/wm/AppWindowToken.java b/services/java/com/android/server/wm/AppWindowToken.java
index 3ae9f24..4b3d904 100644
--- a/services/java/com/android/server/wm/AppWindowToken.java
+++ b/services/java/com/android/server/wm/AppWindowToken.java
@@ -222,7 +222,7 @@
 
     // This must be called while inside a transaction.
     boolean stepAnimationLocked(long currentTime, int dw, int dh) {
-        if (!service.mDisplayFrozen && service.mPolicy.isScreenOnFully()) {
+        if (service.okToDisplay()) {
             // We will run animations as long as the display isn't frozen.
 
             if (animation == WindowManagerService.sDummyAnimation) {