client: disable channel idleness by default (#6328)

dialoptions.go

@@ -628,7 +628,6 @@ func defaultDialOptions() dialOptions {
 			ReadBufferSize:  defaultReadBufSize,
 			UseProxy:        true,
 		},
-		idleTimeout: 30 * time.Minute,
 	}
 }
 
@@ -665,8 +664,8 @@ func WithResolvers(rs ...resolver.Builder) DialOption {
 // channel will exit idle mode when the Connect() method is called or when an
 // RPC is initiated.
 //
-// A default timeout of 30 min will be used if this dial option is not set at
-// dial time and idleness can be disabled by passing a timeout of zero.
+// By default this feature is disabled, which can also be explicitly configured
+// by passing zero to this function.
 //
 // # Experimental
 //