Convert USE_PROPRIETARY_CODECS to a buildflag header.

content/browser/media/media_redirect_browsertest.cc

Index: content/browser/media/media_redirect_browsertest.cc
diff --git a/content/browser/media/media_redirect_browsertest.cc b/content/browser/media/media_redirect_browsertest.cc
index cc8a02949512e7166b5bfa3e84071bf42fdca194..93b1ce4627636f22286ef32f4490b8c346329062 100644
--- a/content/browser/media/media_redirect_browsertest.cc
+++ b/content/browser/media/media_redirect_browsertest.cc
@@ -7,6 +7,7 @@
 #include "content/public/test/browser_test_utils.h"
 #include "content/public/test/content_browser_test_utils.h"
 #include "media/base/test_data_util.h"
+#include "media/media_features.h"
 #include "net/test/embedded_test_server/embedded_test_server.h"
 #include "net/test/embedded_test_server/http_request.h"
 #include "net/test/embedded_test_server/http_response.h"
@@ -59,7 +60,7 @@ IN_PROC_BROWSER_TEST_F(MediaRedirectTest, CanPlayHiddenWebm) {
   RunRedirectTest("bear.webm");
 }
 
-#if defined(OS_ANDROID) && defined(USE_PROPRIETARY_CODECS)
+#if defined(OS_ANDROID) && BUILDFLAG(USE_PROPRIETARY_CODECS)
 // Flaky, see http://crbug.com/624005
 IN_PROC_BROWSER_TEST_F(MediaRedirectTest, DISABLED_CanPlayHiddenHls) {
   RunRedirectTest("bear.m3u8");