Added AEC3 parameter for specifying that the setup has clock drift

Bug: webrtc:8940
Change-Id: Ic29af185ecb212d7d27bafc8432033bdd35c6d3b
Reviewed-on: https://webrtc-review.googlesource.com/58060
Reviewed-by: Gustaf Ullberg <gustaf@webrtc.org>
Commit-Queue: Per Åhgren <peah@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22199}

api/audio/echo_canceller3_config.h

@@ -114,6 +114,8 @@ struct EchoCanceller3Config {
       int non_zero_gain_blocks = 187;
       int full_gain_blocks = 312;
     } gain_rampup;
+
+    bool has_clock_drift = false;
   } echo_removal_control;
 };
 }  // namespace webrtc