Mojo: Rename (Mojo)WaitFlagsState -> (Mojo)HandleSignalsState.

mojo/system/waiter_list.h

Index: mojo/system/waiter_list.h
diff --git a/mojo/system/waiter_list.h b/mojo/system/waiter_list.h
index 62d05d1d40f3bdfa974fb179fd1ce18978c18caf..39ac7b0010063da32b1d9975a6d16235f81da4f7 100644
--- a/mojo/system/waiter_list.h
+++ b/mojo/system/waiter_list.h
@@ -17,7 +17,7 @@ namespace mojo {
 namespace system {
 
 class Waiter;
-struct WaitFlagsState;
+struct HandleSignalsState;
 
 // |WaiterList| tracks all the |Waiter|s that are waiting on a given
 // handle/|Dispatcher|. There should be a |WaiterList| for each handle that can
@@ -31,7 +31,7 @@ class MOJO_SYSTEM_IMPL_EXPORT WaiterList {
   WaiterList();
   ~WaiterList();
 
-  void AwakeWaitersForStateChange(const WaitFlagsState& state);
+  void AwakeWaitersForStateChange(const HandleSignalsState& state);
   void CancelAllWaiters();
   void AddWaiter(Waiter* waiter, MojoHandleSignals signals, uint32_t context);
   void RemoveWaiter(Waiter* waiter);