Change initial DTLS retransmission timer from 1 second to 50ms.

webrtc/base/timeutils.cc

Index: webrtc/base/timeutils.cc
diff --git a/webrtc/base/timeutils.cc b/webrtc/base/timeutils.cc
index 3c89d808b39f97f6e2a8ace502c04d769269670d..1be368eb5847a95cca75833ee0e4d0e57644afcd 100644
--- a/webrtc/base/timeutils.cc
+++ b/webrtc/base/timeutils.cc
@@ -38,10 +38,7 @@ ClockInterface* SetClockForTesting(ClockInterface* clock) {
   return prev;
 }
 
-uint64_t TimeNanos() {
-  if (g_clock) {
-    return g_clock->TimeNanos();
-  }
+uint64_t SystemTimeNanos() {
   int64_t ticks;
 #if defined(WEBRTC_MAC)
   static mach_timebase_info_data_t timebase;
@@ -86,6 +83,17 @@ uint64_t TimeNanos() {
   return ticks;
 }
 
+int64_t SystemTimeMillis() {
+  return static_cast<int64_t>(SystemTimeNanos() / kNumNanosecsPerMillisec);
+}
+
+uint64_t TimeNanos() {
+  if (g_clock) {
+    return g_clock->TimeNanos();
+  }
+  return SystemTimeNanos();
+}
+
 uint32_t Time32() {
   return static_cast<uint32_t>(TimeNanos() / kNumNanosecsPerMillisec);
 }