Move video_replay under rtc_tools/.

As pointed out in [1], RTC public tools should live in rtc_tools.

[1] - https://webrtc-review.googlesource.com/c/src/+/168320/2#message-1f40103105ecb077aeec153c5270575138349a50

Bug: chromium:942546
Change-Id: Ic827d9b31ade9a32bf4ef24d020ef8c81d2c9a5b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/168308
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30486}
diff --git a/BUILD.gn b/BUILD.gn
index 24dc067..12ba794 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -56,13 +56,13 @@
         "pc:peerconnection_unittests",
         "pc:rtc_pc_unittests",
         "rtc_tools:rtp_generator",
+        "rtc_tools:video_replay",
         "stats:rtc_stats_unittests",
         "system_wrappers:system_wrappers_unittests",
         "test",
         "video:screenshare_loopback",
         "video:sv_loopback",
         "video:video_loopback",
-        "video:video_replay",
       ]
       if (!is_asan) {
         # Do not build :webrtc_lib_link_test because lld complains on some OS