Replace Atomic32 with webrtc/base/atomicops.h.

webrtc/system_wrappers/interface/ref_count.h

Index: webrtc/system_wrappers/interface/ref_count.h
diff --git a/webrtc/system_wrappers/interface/ref_count.h b/webrtc/system_wrappers/interface/ref_count.h
index 68616662e906a1c96095e5d401047bbfb84bd317..7ff963dd1abf06d1b4cee1c37cc8421e3c39e2b6 100644
--- a/webrtc/system_wrappers/interface/ref_count.h
+++ b/webrtc/system_wrappers/interface/ref_count.h
@@ -11,7 +11,7 @@
 #ifndef SYSTEM_WRAPPERS_INTERFACE_REF_COUNT_H_
 #define SYSTEM_WRAPPERS_INTERFACE_REF_COUNT_H_
 
-#include "webrtc/system_wrappers/interface/atomic32.h"
+#include "webrtc/base/atomicops.h"
 
 namespace webrtc {
 
@@ -61,20 +61,18 @@ class RefCountImpl : public T {
   RefCountImpl(P1 p1, P2 p2, P3 p3, P4 p4, P5 p5)
       : T(p1, p2, p3, p4, p5), ref_count_(0) {}
 
-  virtual int32_t AddRef() {
-    return ++ref_count_;
-  }
+  virtual int32_t AddRef() { return rtc::AtomicOps::Increment(&ref_count_); }
 
   virtual int32_t Release() {
     int32_t ref_count;
-    ref_count = --ref_count_;
+    ref_count = rtc::AtomicOps::Decrement(&ref_count_);
     if (ref_count == 0)
       delete this;
     return ref_count;
   }
 
  protected:
-  Atomic32 ref_count_;
+  volatile int ref_count_;
 };
 
 }  // namespace webrtc