Delete all use of tick_util.h.

Depends on Chrome cl https://codereview.chromium.org/1888003002/, which was landed some time ago.

BUG=webrtc:5740
R=stefan@webrtc.org, tommi@webrtc.org

Review URL: https://codereview.webrtc.org/1888593004 .

Cr-Commit-Position: refs/heads/master@{#12674}
diff --git a/webrtc/system_wrappers/source/condition_variable_unittest.cc b/webrtc/system_wrappers/source/condition_variable_unittest.cc
index bf245e6..5fc6bc6 100644
--- a/webrtc/system_wrappers/source/condition_variable_unittest.cc
+++ b/webrtc/system_wrappers/source/condition_variable_unittest.cc
@@ -17,8 +17,8 @@
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "webrtc/base/platform_thread.h"
+#include "webrtc/base/timeutils.h"
 #include "webrtc/system_wrappers/include/critical_section_wrapper.h"
-#include "webrtc/system_wrappers/include/tick_util.h"
 #include "webrtc/system_wrappers/include/trace.h"
 
 namespace webrtc {
@@ -191,9 +191,9 @@
   InitializeCriticalSection(&crit_sect);
   ConditionVariableEventWin cond_var;
   EnterCriticalSection(&crit_sect);
-  int64_t start_ms = TickTime::MillisecondTimestamp();
+  int64_t start_ms = rtc::TimeMillis();
   EXPECT_FALSE(cond_var.SleepCS(&crit_sect, kVeryShortWaitMs));
-  int64_t end_ms = TickTime::MillisecondTimestamp();
+  int64_t end_ms = rtc::TimeMillis();
   EXPECT_LE(start_ms + kVeryShortWaitMs, end_ms)
       << "actual elapsed:" << end_ms - start_ms;
   LeaveCriticalSection(&crit_sect);