add missing includes

Summary: add missing includes in folly fibers.q

Reviewed By: A5he

Differential Revision: D4036830

fbshipit-source-id: 4dcb87377979f2875ba31b4869c2637a82298957

folly/fibers/BatchDispatcher.h

@@ -15,8 +15,13 @@
  */
 #pragma once
 
+#include <folly/Function.h>
 #include <folly/futures/Future.h>
 #include <folly/futures/Promise.h>
+#include <exception>
+#include <memory>
+#include <stdexcept>
+#include <vector>
 
 namespace folly {
 namespace fibers {

folly/fibers/WhenN.h

@@ -15,7 +15,11 @@
  */
 #pragma once
 
+#include <iterator>
 #include <memory>
+#include <type_traits>
+#include <utility>
+#include <vector>
 
 namespace folly {
 namespace fibers {