Move enable_webrtc to a buildflag header.

chrome/browser/extensions/api/preference/preference_apitest.cc

Index: chrome/browser/extensions/api/preference/preference_apitest.cc
diff --git a/chrome/browser/extensions/api/preference/preference_apitest.cc b/chrome/browser/extensions/api/preference/preference_apitest.cc
index 6d2a5bad5bb45599fb7136f66f1bd77cfd38b5a6..d6b92a2b83c8380d3979752304bf0c86c62fb096 100644
--- a/chrome/browser/extensions/api/preference/preference_apitest.cc
+++ b/chrome/browser/extensions/api/preference/preference_apitest.cc
@@ -32,6 +32,7 @@
 #include "extensions/browser/test_extension_registry_observer.h"
 #include "extensions/test/extension_test_message_listener.h"
 #include "extensions/test/result_catcher.h"
+#include "media/media_features.h"
 
 class ExtensionPreferenceApiTest : public ExtensionApiTest {
  protected:
@@ -126,7 +127,7 @@ IN_PROC_BROWSER_TEST_F(ExtensionPreferenceApiTest, MAYBE_Standard) {
                     false);
   prefs->SetBoolean(prefs::kSafeBrowsingEnabled, false);
   prefs->SetBoolean(prefs::kSearchSuggestEnabled, false);
-#if defined(ENABLE_WEBRTC)
+#if BUILDFLAG(ENABLE_WEBRTC)
   prefs->SetBoolean(prefs::kWebRTCMultipleRoutesEnabled, false);
   prefs->SetBoolean(prefs::kWebRTCNonProxiedUdpEnabled, false);
   prefs->SetString(prefs::kWebRTCIPHandlingPolicy,