Suppress a warning in advance that will be a run-time error in Guice in a subsequent commit, and which will be added to error-prone and caught at compile-time for those who use it.

------------------
Manually Synced.
COMMIT=43228490
diff --git a/extensions/assistedinject/test/com/google/inject/assistedinject/FactoryModuleBuilderTest.java b/extensions/assistedinject/test/com/google/inject/assistedinject/FactoryModuleBuilderTest.java
index 39f039c..f8875c9 100644
--- a/extensions/assistedinject/test/com/google/inject/assistedinject/FactoryModuleBuilderTest.java
+++ b/extensions/assistedinject/test/com/google/inject/assistedinject/FactoryModuleBuilderTest.java
@@ -478,6 +478,7 @@
     AssistedSingleton create(String string);
   }
   
+  @SuppressWarnings("GuiceAssistedInjectScoping")
   @Singleton
   static class AssistedSingleton {
     @Inject