Rationalize AddAwakable...() and RemoveAwakable...() methods.

mojo/edk/system/simple_dispatcher.h

Index: mojo/edk/system/simple_dispatcher.h
diff --git a/mojo/edk/system/simple_dispatcher.h b/mojo/edk/system/simple_dispatcher.h
index 95942cfa0f6c1e8903f711b85a705232f67a4104..eecbf40576d19fe82220b7bb2bec7b00f5df3f1c 100644
--- a/mojo/edk/system/simple_dispatcher.h
+++ b/mojo/edk/system/simple_dispatcher.h
@@ -33,16 +33,14 @@ class SimpleDispatcher : public Dispatcher {
   // |Dispatcher| protected methods:
   void CancelAllStateNoLock() override;
   MojoResult AddAwakableImplNoLock(Awakable* awakable,
-                                   MojoHandleSignals signals,
-                                   bool force,
                                    uint64_t context,
+                                   bool force,
+                                   MojoHandleSignals signals,
                                    HandleSignalsState* signals_state) override;
-  void RemoveAwakableImplNoLock(Awakable* awakable,
+  void RemoveAwakableImplNoLock(bool match_context,
+                                Awakable* awakable,
+                                uint64_t context,
                                 HandleSignalsState* signals_state) override;
-  void RemoveAwakableWithContextImplNoLock(
-      Awakable* awakable,
-      uint64_t context,
-      HandleSignalsState* signals_state) override;
 
  private:
   AwakableList awakable_list_ MOJO_GUARDED_BY(mutex());