Lock scheme #8: Introduced the new locking scheme

webrtc/modules/audio_processing/high_pass_filter_impl.cc

Index: webrtc/modules/audio_processing/high_pass_filter_impl.cc
diff --git a/webrtc/modules/audio_processing/high_pass_filter_impl.cc b/webrtc/modules/audio_processing/high_pass_filter_impl.cc
index 29e482078e9438ba6a0397986ca1c702e865e0ca..8de2162175ca762f502f91ff83188b2cf79a1789 100644
--- a/webrtc/modules/audio_processing/high_pass_filter_impl.cc
+++ b/webrtc/modules/audio_processing/high_pass_filter_impl.cc
@@ -100,14 +100,14 @@ int Filter(FilterState* hpf, int16_t* data, size_t length) {
 typedef FilterState Handle;
 
 HighPassFilterImpl::HighPassFilterImpl(const AudioProcessing* apm,
-                                       CriticalSectionWrapper* crit)
-  : ProcessingComponent(),
-    apm_(apm),
-    crit_(crit) {}
+                                       rtc::CriticalSection* crit)
+    : ProcessingComponent(), apm_(apm), crit_(crit) {}
 
 HighPassFilterImpl::~HighPassFilterImpl() {}
 
 int HighPassFilterImpl::ProcessCaptureAudio(AudioBuffer* audio) {
+  // This function is only called from within APM and does not/cannot
+  // take a lock.
   int err = apm_->kNoError;
 
   if (!is_component_enabled()) {
@@ -131,11 +131,12 @@ int HighPassFilterImpl::ProcessCaptureAudio(AudioBuffer* audio) {
 }
 
 int HighPassFilterImpl::Enable(bool enable) {
-  CriticalSectionScoped crit_scoped(crit_);
+  rtc::CritScope cs(crit_);
   return EnableComponent(enable);
 }
 
 bool HighPassFilterImpl::is_enabled() const {
+  rtc::CritScope cs(crit_);
   return is_component_enabled();
 }
 
@@ -148,6 +149,8 @@ void HighPassFilterImpl::DestroyHandle(void* handle) const {
 }
 
 int HighPassFilterImpl::InitializeHandle(void* handle) const {
+  // TODO(peah): Remove dependency on apm for the
+  // capture side sample rate.
   return InitializeFilter(static_cast<Handle*>(handle),
                           apm_->proc_sample_rate_hz());
 }