Update CQ client lib

third_party/cq_client/cq.proto

 syntax = "proto2";
 
 // This message describes a Commit Queue configuration. The config file cq.cfg
 // should be stored in the config directory located on the branch that this CQ
 // should commit to.
 message Config {
   // Required. Version of the config format.
   optional int32 version = 1;
 
   // Required. Name of the CQ. May only contain characters [a-zA-Z0-9_]. It is
@@ skipping 122 matching lines @@
       optional bool triggered = 2;
 
       // When this field is present, it marks given builder as experimental. It
       // is only executed on a given percentage of the CLs and the outcome does
       // not affect the decicion whether a CL can land or not. This is typically
       // used to test new builders and estimate their capacity requirements.
       optional float experiment_percentage = 4;
     }
 
     message Bucket {
-      // Name of the bucket. This is typically the same as a master name.
+      // Name of the bucket. This is typically the same as a master name without
+      // the 'master.' prefix, e.g. 'chromium.linux' or 'tryserver.webrtc'. CQ
+      // will automatically add 'master.' prefix if not there.
       optional string name = 1;
 
       // Builders on which tryjobs should be triggered.
       repeated Builder builders = 2;
     }
 
     // Buckets on which tryjobs are triggered/watched.
     repeated Bucket buckets = 1;
 
     message TryJobRetryConfig {
@@ skipping 13 matching lines @@
       optional int32 timeout_retry_weight = 5;
     }
 
     // Provides project specific trybot retry configuration. This overrides the
     // defaults used in the CQ.
     optional TryJobRetryConfig try_job_retry_config = 2;
   }
 
   message SignCLAVerifier {}
 }