Swap use of CriticalSectionWrapper with rtc::CriticalSection in voice_engine/
Also remove mischievous tab character!
This is a part of getting rid of CriticalSectionWrapper and makes the code slightly simpler.

BUG=

Review URL: https://codereview.webrtc.org/1607353002

Cr-Commit-Position: refs/heads/master@{#11346}
diff --git a/webrtc/voice_engine/monitor_module.h b/webrtc/voice_engine/monitor_module.h
index fe915b3..5539915 100644
--- a/webrtc/voice_engine/monitor_module.h
+++ b/webrtc/voice_engine/monitor_module.h
@@ -11,6 +11,8 @@
 #ifndef WEBRTC_VOICE_ENGINE_MONITOR_MODULE_H
 #define WEBRTC_VOICE_ENGINE_MONITOR_MODULE_H
 
+#include "webrtc/base/criticalsection.h"
+#include "webrtc/base/thread_annotations.h"
 #include "webrtc/modules/include/module.h"
 #include "webrtc/typedefs.h"
 #include "webrtc/voice_engine/voice_engine_defines.h"
@@ -25,8 +27,6 @@
 
 
 namespace webrtc {
-class CriticalSectionWrapper;
-
 namespace voe {
 
 class MonitorModule : public Module
@@ -45,8 +45,8 @@
  int32_t Process() override;
 
 private:
-    MonitorObserver* _observerPtr;
-    CriticalSectionWrapper&	_callbackCritSect;
+    rtc::CriticalSection _callbackCritSect;
+    MonitorObserver* _observerPtr GUARDED_BY(_callbackCritSect);
     int64_t _lastProcessTime;
 };