Handle vmservice messages while at breakpoint.

runtime/include/dart_api.h

 /*
  * Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
  * for details. All rights reserved. Use of this source code is governed by a
  * BSD-style license that can be found in the LICENSE file.
  */
 
 #ifndef INCLUDE_DART_API_H_
 #define INCLUDE_DART_API_H_
 
 /** \mainpage Dart Embedding API Reference
@@ skipping 965 matching lines @@
 /**
  * Handles the next pending message for the current isolate.
  *
  * May generate an unhandled exception error.
  *
  * \return A valid handle if no error occurs during the operation.
  */
 DART_EXPORT Dart_Handle Dart_HandleMessage();
 
 /**
+ * Handles any pending messages for the vm service for the current
+ * isolate.
+ *
+ * This function may be used by an embedder at a breakpoint to avoid
+ * pausing the vm service.
+ *
+ * \return true if the vm service requests the program resume
+ * execution, false otherwise
+ */
+DART_EXPORT bool Dart_HandleServiceMessages();
+
+/**
  * Processes any incoming messages for the current isolate.
  *
  * This function may only be used when the embedder has not provided
  * an alternate message delivery mechanism with
  * Dart_SetMessageCallbacks. It is provided for convenience.
  *
  * This function waits for incoming messages for the current
  * isolate. As new messages arrive, they are handled using
  * Dart_HandleMessage. The routine exits when all ports to the
  * current isolate are closed.
@@ skipping 1349 matching lines @@
  *
  * \param object An object.
  * \param peer A value to store in the peer field.
  *
  * \return Returns an error if 'object' is a subtype of Null, num, or
  *   bool.
  */
 DART_EXPORT Dart_Handle Dart_SetPeer(Dart_Handle object, void* peer);
 
 #endif  /* INCLUDE_DART_API_H_ */  /* NOLINT */