Option to enable StrictMode flashing on userdebug builds.

Change-Id: Ifc8e733ea0e0f6bda234a18ad84bcd230879e802
diff --git a/services/java/com/android/server/WindowManagerService.java b/services/java/com/android/server/WindowManagerService.java
index 5c32c38..89512ae 100644
--- a/services/java/com/android/server/WindowManagerService.java
+++ b/services/java/com/android/server/WindowManagerService.java
@@ -4918,6 +4918,10 @@
         }
     }
 
+    public void setStrictModeVisualIndicatorPreference(String value) {
+        SystemProperties.set(StrictMode.VISUAL_PROPERTY, value);
+    }
+
     public void freezeRotation() {
         if (!checkCallingPermission(android.Manifest.permission.SET_ORIENTATION,
                 "setRotation()")) {