Update WebRTC code version (2020-12-24T04:03:38).

TBR=webrtc-version-updater@webrtc-ci.iam.gserviceaccount.com,mbonadei@webrtc.org

Bug: None
Change-Id: I13a042f22d6eca961a64e273bbd9b9ef010dddec
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/199081
Reviewed-by: webrtc-version-updater@webrtc-ci.iam.gserviceaccount.com <webrtc-version-updater@webrtc-ci.iam.gserviceaccount.com>
Commit-Queue: webrtc-version-updater@webrtc-ci.iam.gserviceaccount.com <webrtc-version-updater@webrtc-ci.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#32878}
diff --git a/call/version.cc b/call/version.cc
index 9cdbfa4..475a7cc 100644
--- a/call/version.cc
+++ b/call/version.cc
@@ -13,7 +13,7 @@
 namespace webrtc {
 
 // The timestamp is always in UTC.
-const char* const kSourceTimestamp = "WebRTC source stamp 2020-12-21T04:04:21";
+const char* const kSourceTimestamp = "WebRTC source stamp 2020-12-24T04:03:38";
 
 void LoadWebRTCVersionInRegister() {
   // Using volatile to instruct the compiler to not optimize `p` away even