Mojo EDK: Introduce MojoQueryHandleSignalsState API

mojo/public/c/system/thunks.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Note: This header should be compilable as C.
 
 #ifndef MOJO_PUBLIC_C_SYSTEM_THUNKS_H_
 #define MOJO_PUBLIC_C_SYSTEM_THUNKS_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include "mojo/public/c/system/core.h"
 #include "mojo/public/c/system/system_export.h"
 
 // Structure used to bind the basic Mojo Core functions to an embedder
 // implementation. This is intended to eventually be used as a stable ABI
 // between a Mojo embedder and some loaded application code, but for now it is
 // still effectively safe to rearrange entries as needed.
 #pragma pack(push, 8)
 struct MojoSystemThunks {
   size_t size;  // Should be set to sizeof(MojoSystemThunks).
   MojoTimeTicks (*GetTimeTicksNow)();
   MojoResult (*Close)(MojoHandle handle);
+  MojoResult (*QueryHandleSignalsState)(
+      MojoHandle handle,
+      struct MojoHandleSignalsState* signals_state);
   MojoResult (*Wait)(MojoHandle handle,
                      MojoHandleSignals signals,
                      MojoDeadline deadline,
                      struct MojoHandleSignalsState* signals_state);
   MojoResult (*WaitMany)(const MojoHandle* handles,
                          const MojoHandleSignals* signals,
                          uint32_t num_handles,
                          MojoDeadline deadline,
                          uint32_t* result_index,
                          struct MojoHandleSignalsState* signals_states);
@@ skipping 123 matching lines @@
 // The contents of |system_thunks| are copied.
 typedef size_t (*MojoSetSystemThunksFn)(
     const struct MojoSystemThunks* system_thunks);
 
 // A function for setting up the embedder's own system thunks. This should only
 // be called by Mojo embedder code.
 MOJO_SYSTEM_EXPORT size_t MojoEmbedderSetSystemThunks(
     const struct MojoSystemThunks* system_thunks);
 
 #endif  // MOJO_PUBLIC_C_SYSTEM_THUNKS_H_