Removes all const Clock*.

This prepares for making the Clock interface fully mutable.

Calls to the time functions in Clock can have side effects in some
circumstances. It's also questionable if it's a good idea to allow
repeated calls to a const method return different values without
any changed to the class instance.

Bug: webrtc:9883
Change-Id: I96fb9230705f7c80a4c0702132fd9dc73899fc5e
Reviewed-on: https://webrtc-review.googlesource.com/c/120347
Commit-Queue: Sebastian Jansson <srte@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26467}
diff --git a/call/rtp_transport_controller_send.cc b/call/rtp_transport_controller_send.cc
index 777d7f8..31e1334 100644
--- a/call/rtp_transport_controller_send.cc
+++ b/call/rtp_transport_controller_send.cc
@@ -35,7 +35,7 @@
 TargetRateConstraints ConvertConstraints(int min_bitrate_bps,
                                          int max_bitrate_bps,
                                          int start_bitrate_bps,
-                                         const Clock* clock) {
+                                         Clock* clock) {
   TargetRateConstraints msg;
   msg.at_time = Timestamp::ms(clock->TimeInMilliseconds());
   msg.min_data_rate =
@@ -48,7 +48,7 @@
 }
 
 TargetRateConstraints ConvertConstraints(const BitrateConstraints& contraints,
-                                         const Clock* clock) {
+                                         Clock* clock) {
   return ConvertConstraints(contraints.min_bitrate_bps,
                             contraints.max_bitrate_bps,
                             contraints.start_bitrate_bps, clock);