Preparational work for an upcoming addition of a threadchecking scheme for APM

webrtc/modules/audio_processing/echo_control_mobile_impl.cc

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 50 matching lines @@
 // Maximum number of frames to buffer in the render queue.
 // TODO(peah): Decrease this once we properly handle hugely unbalanced
 // reverse and forward call numbers.
 static const size_t kMaxNumFramesToBuffer = 100;
 }  // namespace
 
 size_t EchoControlMobile::echo_path_size_bytes() {
     return WebRtcAecm_echo_path_size_bytes();
 }
 
-EchoControlMobileImpl::EchoControlMobileImpl(const AudioProcessing* apm,
-                                             CriticalSectionWrapper* crit)
+EchoControlMobileImpl::EchoControlMobileImpl(
+    const AudioProcessing* apm,
+    CriticalSectionWrapper* crit,
+    const rtc::ThreadChecker* render_thread_checker)
     : ProcessingComponent(),
       apm_(apm),
       crit_(crit),
+      render_thread_checker_(render_thread_checker),
       routing_mode_(kSpeakerphone),
       comfort_noise_enabled_(true),
       external_echo_path_(NULL),
       render_queue_element_max_size_(0) {}
 
 EchoControlMobileImpl::~EchoControlMobileImpl() {
     if (external_echo_path_ != NULL) {
       delete [] external_echo_path_;
       external_echo_path_ = NULL;
     }
 }
 
 int EchoControlMobileImpl::ProcessRenderAudio(const AudioBuffer* audio) {
+  RTC_DCHECK(render_thread_checker_->CalledOnValidThread());
   if (!is_component_enabled()) {
     return apm_->kNoError;
   }
 
   assert(audio->num_frames_per_band() <= 160);
   assert(audio->num_channels() == apm_->num_reverse_channels());
 
   int err = apm_->kNoError;
 
   // The ordering convention must be followed to pass to the correct AECM.
@@ skipping 262 matching lines @@
 int EchoControlMobileImpl::num_handles_required() const {
   return apm_->num_output_channels() *
          apm_->num_reverse_channels();
 }
 
 int EchoControlMobileImpl::GetHandleError(void* handle) const {
   assert(handle != NULL);
   return AudioProcessing::kUnspecifiedError;
 }
 }  // namespace webrtc