Replace remaining gflags usages with rtc_base/flags

webrtc/voice_engine/test/auto_test/standard/rtp_rtcp_test.cc

Index: webrtc/voice_engine/test/auto_test/standard/rtp_rtcp_test.cc
diff --git a/webrtc/voice_engine/test/auto_test/standard/rtp_rtcp_test.cc b/webrtc/voice_engine/test/auto_test/standard/rtp_rtcp_test.cc
index 9af7f8653aaa1ab51124e0c2c0d37f86bd5b9c74..24bb0a7ed39c9d91701dd34524061179fe426704 100644
--- a/webrtc/voice_engine/test/auto_test/standard/rtp_rtcp_test.cc
+++ b/webrtc/voice_engine/test/auto_test/standard/rtp_rtcp_test.cc
@@ -11,11 +11,14 @@
 #include <memory>
 
 #include "webrtc/rtc_base/criticalsection.h"
+#include "webrtc/rtc_base/flags.h"
 #include "webrtc/system_wrappers/include/event_wrapper.h"
 #include "webrtc/test/testsupport/fileutils.h"
 #include "webrtc/voice_engine/test/auto_test/fixtures/after_streaming_fixture.h"
 #include "webrtc/voice_engine/test/auto_test/voe_standard_test.h"
 
+DECLARE_bool(include_timing_dependent_tests);
+
 class TestRtpObserver : public webrtc::VoERTPObserver {
  public:
   TestRtpObserver() : changed_ssrc_event_(webrtc::EventWrapper::Create()) {}
@@ -85,7 +88,7 @@ class RtpRtcpTest : public AfterStreamingFixture {
 };
 
 TEST_F(RtpRtcpTest, RemoteRtcpCnameHasPropagatedToRemoteSide) {
-  if (!FLAGS_include_timing_dependent_tests) {
+  if (!FLAG_include_timing_dependent_tests) {
     TEST_LOG("Skipping test - running in slow execution environment...\n");
     return;
   }