Clean comments, namespace, and variable names

This CL removes TODOs and email addresses from comments, unifies some
namespaces and cleans a few variable names.  It is a copy of multiple
CLs on the widevine side.

Change-Id: I1bb649096476a5001a56d746427399de6a88ff69

libwvdrmengine/cdm/core/include/cdm_engine.h

@@ -1,7 +1,7 @@
 // Copyright 2013 Google Inc. All Rights Reserved.
 
-#ifndef CDM_BASE_CDM_ENGINE_H_
-#define CDM_BASE_CDM_ENGINE_H_
+#ifndef WVCDM_CORE_CDM_ENGINE_H_
+#define WVCDM_CORE_CDM_ENGINE_H_
 
 #include "certificate_provisioning.h"
 #include "initialization_data.h"
@@ -132,4 +132,4 @@ class CdmEngine {
 
 }  // namespace wvcdm
 
-#endif  // CDM_BASE_CDM_ENGINE_H_
+#endif  // WVCDM_CORE_CDM_ENGINE_H_