EDK: Add implementation of data pipe consumer read threshold stuff.

mojo/edk/system/core.h

 // Copyright 2013 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.
 
 #ifndef MOJO_EDK_SYSTEM_CORE_H_
 #define MOJO_EDK_SYSTEM_CORE_H_
 
 #include <stdint.h>
 
 #include <functional>
@@ skipping 122 matching lines @@
   MojoResult WriteData(MojoHandle data_pipe_producer_handle,
                        UserPointer<const void> elements,
                        UserPointer<uint32_t> num_bytes,
                        MojoWriteDataFlags flags);
   MojoResult BeginWriteData(MojoHandle data_pipe_producer_handle,
                             UserPointer<void*> buffer,
                             UserPointer<uint32_t> buffer_num_bytes,
                             MojoWriteDataFlags flags);
   MojoResult EndWriteData(MojoHandle data_pipe_producer_handle,
                           uint32_t num_bytes_written);
+  MojoResult SetDataPipeConsumerOptions(
+      MojoHandle data_pipe_consumer_handle,
+      UserPointer<const MojoDataPipeConsumerOptions> options);
+  MojoResult GetDataPipeConsumerOptions(
+      MojoHandle data_pipe_consumer_handle,
+      UserPointer<MojoDataPipeConsumerOptions> options,
+      uint32_t options_num_bytes);
   MojoResult ReadData(MojoHandle data_pipe_consumer_handle,
                       UserPointer<void> elements,
                       UserPointer<uint32_t> num_bytes,
                       MojoReadDataFlags flags);
   MojoResult BeginReadData(MojoHandle data_pipe_consumer_handle,
                            UserPointer<const void*> buffer,
                            UserPointer<uint32_t> buffer_num_bytes,
                            MojoReadDataFlags flags);
   MojoResult EndReadData(MojoHandle data_pipe_consumer_handle,
                          uint32_t num_bytes_read);
@@ skipping 42 matching lines @@
   util::Mutex mapping_table_mutex_;
   MappingTable mapping_table_ MOJO_GUARDED_BY(mapping_table_mutex_);
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(Core);
 };
 
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_EDK_SYSTEM_CORE_H_