Remove all uses of the HAVE_CONFIG_H define.

webrtc/media/base/mediaengine.cc

Index: webrtc/media/base/mediaengine.cc
diff --git a/webrtc/media/base/mediaengine.cc b/webrtc/media/base/mediaengine.cc
index 4027137565e10a179688e0c0283835e65eb95cc3..fda7fac1a9343701cf770e92d8d119f57d5c8a0d 100644
--- a/webrtc/media/base/mediaengine.cc
+++ b/webrtc/media/base/mediaengine.cc
@@ -16,10 +16,6 @@
 #include "webrtc/media/engine/webrtcmediaengine.h"
 #endif  // HAVE_WEBRTC_VOICE && HAVE_WEBRTC_VIDEO
 
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif  // HAVE_CONFIG
-
 namespace cricket {
 
 MediaEngineFactory::MediaEngineCreateFunction
@@ -45,4 +41,4 @@ webrtc::RtpParameters CreateRtpParametersWithOneEncoding() {
   return parameters;
 }
 
-};  // namespace cricket
+};  // namespace cricket