Allow suspend extensions for specially annotated controllers

libraries/tools/binary-compatibility-validator/reference-public-api/kotlin-runtime.txt

@@ -164,6 +164,9 @@ public abstract class kotlin/collections/ShortIterator : java/util/Iterator, kot
 	public fun remove ()V
 }
 
+public abstract interface annotation class kotlin/coroutines/AllowSuspendExtensions : java/lang/annotation/Annotation {
+}
+
 public abstract interface class kotlin/coroutines/Continuation {
 	public abstract fun resume (Ljava/lang/Object;)V
 	public abstract fun resumeWithException (Ljava/lang/Throwable;)V