Enable cpplint for webrtc/examples and fix all uncovered cpplint errors.

webrtc/examples/peerconnection/server/peer_channel.h

Index: webrtc/examples/peerconnection/server/peer_channel.h
diff --git a/webrtc/examples/peerconnection/server/peer_channel.h b/webrtc/examples/peerconnection/server/peer_channel.h
index 263f17dfa88f5aeb06785ecf07b35fe457087c64..6fd740d2f9a79964f7553fd4c14499135f20ae18 100644
--- a/webrtc/examples/peerconnection/server/peer_channel.h
+++ b/webrtc/examples/peerconnection/server/peer_channel.h
@@ -8,8 +8,8 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#ifndef TALK_EXAMPLES_PEERCONNECTION_SERVER_PEER_CHANNEL_H_
-#define TALK_EXAMPLES_PEERCONNECTION_SERVER_PEER_CHANNEL_H_
+#ifndef WEBRTC_EXAMPLES_PEERCONNECTION_SERVER_PEER_CHANNEL_H_
+#define WEBRTC_EXAMPLES_PEERCONNECTION_SERVER_PEER_CHANNEL_H_
 #pragma once
 
 #include <time.h>
@@ -117,4 +117,4 @@ class PeerChannel {
   Members members_;
 };
 
-#endif  // TALK_EXAMPLES_PEERCONNECTION_SERVER_PEER_CHANNEL_H_
+#endif  // WEBRTC_EXAMPLES_PEERCONNECTION_SERVER_PEER_CHANNEL_H_