SpeechInputExtensionManager now interface with SpeechRecognitionManagerDelegate

content/browser/speech/speech_recognition_manager_impl.cc

 // Copyright (c) 2012 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.
 
 #include "content/browser/speech/speech_recognition_manager_impl.h"
 
 #include "base/bind.h"
 #include "content/browser/browser_main_loop.h"
 #include "content/browser/speech/google_one_shot_remote_engine.h"
 #include "content/browser/speech/speech_recognition_engine.h"
@@ skipping 309 matching lines @@
       AbortSession(session.id);
       session.listener_is_active = false;
     }
   }
 }
 
 // -----------------------  Core FSM implementation ---------------------------
 void SpeechRecognitionManagerImpl::DispatchEvent(int session_id,
                                                  FSMEvent event) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  // There are some corner cases in which the session might be deleted (due to
+  // an EndRecognition event) between a request (e.g. Abort) and its dispatch.

[Satish, 2012/05/20 21:40:26]

In any of these cases, does the caller need to be informed by a callback that
their request has completed (even though the session is already gone) ?

[Primiano Tucci (use gerrit), 2012/05/21 16:03:13]

As a general reply, every caller (delegate) receives always a notification,
through, the OnRecognitionEnd event, when a session terminates (thus is
deleted).
This comment, however, refers to the cases of double Aborts, e.g., one internal
(issued by the caller) and one external. Some cases in which this can happen
are, for instance:

- Browser shutdown: the AbortAllSessionsForListener method is called to abort
the pending sessions, however, the session narually terminates in the meanwhile
(so at the time in which this posted function is executed the session has
already gone)

- A user clicks on a x-webkit-speech input while a session is going on for an
extension (so the extension's session is aborted) but the session ends in the
meanwhile.

+  if (!SessionExists(session_id))
+    return;
+
   const Session& session = GetSession(session_id);
   FSMState session_state = GetSessionState(session_id);
   DCHECK_LE(session_state, SESSION_STATE_MAX_VALUE);
   DCHECK_LE(event, EVENT_MAX_VALUE);
 
   // Event dispatching must be sequential, otherwise it will break all the rules
   // and the assumptions of the finite state automata model.
   DCHECK(!is_dispatching_event_);
   is_dispatching_event_ = true;
   ExecuteTransitionAndGetNextState(session, session_state, event);
@@ skipping 178 matching lines @@
 
 SpeechRecognitionManagerImpl::Session::Session()
   : id(kSessionIDInvalid),
     listener_is_active(true) {
 }
 
 SpeechRecognitionManagerImpl::Session::~Session() {
 }
 
 }  // namespace speech