Delete old video defines in engine config.

This CL deletes the old and not used video defines in
engine_configurations.h and pre-pends voice_ to indicate there are only
voice/audio defines left in the file.

BUG=none
R=solenberg@webrtc.org

Review URL: https://codereview.webrtc.org/2401673002 .

Cr-Commit-Position: refs/heads/master@{#14558}
diff --git a/webrtc/modules/audio_coding/test/APITest.cc b/webrtc/modules/audio_coding/test/APITest.cc
index 717de82..ffa675c 100644
--- a/webrtc/modules/audio_coding/test/APITest.cc
+++ b/webrtc/modules/audio_coding/test/APITest.cc
@@ -22,13 +22,13 @@
 #include "webrtc/base/platform_thread.h"
 #include "webrtc/base/timeutils.h"
 #include "webrtc/common_types.h"
-#include "webrtc/engine_configurations.h"
 #include "webrtc/modules/audio_coding/acm2/acm_common_defs.h"
 #include "webrtc/modules/audio_coding/test/utility.h"
 #include "webrtc/system_wrappers/include/event_wrapper.h"
 #include "webrtc/system_wrappers/include/trace.h"
 #include "webrtc/test/gtest.h"
 #include "webrtc/test/testsupport/fileutils.h"
+#include "webrtc/voice_engine_configurations.h"
 
 namespace webrtc {