Delete all use of tick_util.h.

webrtc/modules/rtp_rtcp/source/ssrc_database.cc

 /*
  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #include "webrtc/modules/rtp_rtcp/source/ssrc_database.h"
-
+#include "webrtc/base/timeutils.h"
 #include "webrtc/base/checks.h"
-#include "webrtc/system_wrappers/include/tick_util.h"
 
 namespace webrtc {
 
 SSRCDatabase* SSRCDatabase::GetSSRCDatabase() {
   return GetStaticInstance<SSRCDatabase>(kAddRef);
 }
 
 void SSRCDatabase::ReturnSSRCDatabase() {
   GetStaticInstance<SSRCDatabase>(kRelease);
 }
@@ skipping 13 matching lines @@
 void SSRCDatabase::RegisterSSRC(uint32_t ssrc) {
   rtc::CritScope lock(&crit_);
   ssrcs_.insert(ssrc);
 }
 
 void SSRCDatabase::ReturnSSRC(uint32_t ssrc) {
   rtc::CritScope lock(&crit_);
   ssrcs_.erase(ssrc);
 }
 
-SSRCDatabase::SSRCDatabase() : random_(TickTime::Now().Ticks()) {}
+SSRCDatabase::SSRCDatabase() : random_(rtc::TimeMicros()) {}
 
 SSRCDatabase::~SSRCDatabase() {}
 
 }  // namespace webrtc