[Streaming] Support streaming flow control (#7152)

* streaming writer use event driven model.

* add RefreshChannelInfo

* fix name

* minor changes according reviewer comments

* Fix according to reviewer's comments

* fix bazel lint

* code polished

* Add more comments

* rename Stop & Start of EventQueue to Freeze and Unfreeze.

* add override

* fix

* fix return value

* support flow control

* add flow control ut in mock transfer

* minor changes according to comments

* add java and python worker adaption

Co-authored-by: wanxing <wanxing.wwx@alibaba-inc.com>

streaming/src/protobuf/streaming.proto

@@ -11,6 +11,12 @@ enum OperatorType {
   SINK = 3;
 }
 
+enum FlowControlType {
+  UNKNOWN_FLOW_CONTROL_TYPE = 0;
+  UnconsumedSeqFlowControl = 1;
+  NoFlowControl = 2;
+}
+
 // all string in this message is ASCII string
 message StreamingConfig {
   string job_name = 1;
@@ -20,4 +26,8 @@ message StreamingConfig {
   OperatorType role = 5;
   uint32 ring_buffer_capacity = 6;
   uint32 empty_message_interval = 7;
+  FlowControlType flow_control_type = 8;
+  uint32 writer_consumed_step = 9;
+  uint32 reader_consumed_step = 10;
+  uint32 event_driven_flow_control_interval = 11;
 }