[ID Refactor] Refactor ActorID, TaskID and ObjectID (#5286)

* Refactor ActorID, TaskID on the Java side.

Left a TODO comment

WIP for ObjectID

ADD test

Fix

Add java part

Fix Java test

Fix

Refine test.

Enable test in CI

* Extra a helper function.

* Resolve TODOs

* Fix Python CI

* Fix Java lint

* Update .travis.yml

Co-Authored-By: Stephanie Wang <swang@cs.berkeley.edu>

* Address some comments.

Address some comments.

Add id_specification.rst

Reanme id_specification.rst to id_specification.md

typo

Address zhijun's comments.

Fix test

Address comments.

Fix lint

Address comments

* Fix test

* Address comments.

* Fix build error

* Update src/ray/design_docs/id_specification.md

Co-Authored-By: Stephanie Wang <swang@cs.berkeley.edu>

* Update src/ray/design_docs/id_specification.md

Co-Authored-By: Stephanie Wang <swang@cs.berkeley.edu>

* Update src/ray/design_docs/id_specification.md

Co-Authored-By: Stephanie Wang <swang@cs.berkeley.edu>

* Update src/ray/design_docs/id_specification.md

Co-Authored-By: Stephanie Wang <swang@cs.berkeley.edu>

* Update src/ray/design_docs/id_specification.md

Co-Authored-By: Stephanie Wang <swang@cs.berkeley.edu>

* Address comments

* Update src/ray/common/id.h

Co-Authored-By: Stephanie Wang <swang@cs.berkeley.edu>

* Update src/ray/common/id.h

Co-Authored-By: Stephanie Wang <swang@cs.berkeley.edu>

* Update src/ray/common/id.h

Co-Authored-By: Stephanie Wang <swang@cs.berkeley.edu>

* Update src/ray/design_docs/id_specification.md

Co-Authored-By: Hao Chen <chenh1024@gmail.com>

* Update src/ray/design_docs/id_specification.md

Co-Authored-By: Hao Chen <chenh1024@gmail.com>

* Address comments.

* Address comments.

* Address comments.

* Update C++ part to make sure task id is generated determantic

* WIP

* Fix core worker

* Fix Java part

* Fix comments.

* Add Python side

* Fix python

* Address comments

* Fix linting

* Fix

* Fix C++ linting

* Add JobId() method to TaskID

* Fix linting

* Update src/ray/common/id.h

Co-Authored-By: Hao Chen <chenh1024@gmail.com>

* Update java/api/src/main/java/org/ray/api/id/TaskId.java

Co-Authored-By: Hao Chen <chenh1024@gmail.com>

* Update java/api/src/main/java/org/ray/api/id/TaskId.java

Co-Authored-By: Hao Chen <chenh1024@gmail.com>

* Update java/api/src/main/java/org/ray/api/id/ActorId.java

Co-Authored-By: Hao Chen <chenh1024@gmail.com>

* Address comments

* Add DriverTaskId embeding job id

* Fix tests

* Add python dor_fake_driver_id

* Address comments and fix linting

* Fix CI

python/ray/worker.py

@@ -200,7 +200,7 @@ class Worker(object):
                 # to the current task ID may not be correct. Generate a
                 # random task ID so that the backend can differentiate
                 # between different threads.
-                self._task_context.current_task_id = TaskID.from_random()
+                self._task_context.current_task_id = TaskID.for_fake_task()
                 if getattr(self, "_multithreading_warned", False) is not True:
                     logger.warning(
                         "Calling ray.get or ray.wait in a separate thread "
@@ -718,7 +718,24 @@ class Worker(object):
             function_descriptor_list = (
                 function_descriptor.get_function_descriptor_list())
             assert isinstance(job_id, JobID)
+
+            if actor_creation_id is not None and not actor_creation_id.is_nil(
+            ):
+                # This is an actor creation task.
+                task_id = TaskID.for_actor_creation_task(actor_creation_id)
+            elif actor_id is not None and not actor_id.is_nil():
+                # This is an actor task.
+                task_id = TaskID.for_actor_task(
+                    self.current_job_id, self.current_task_id,
+                    self.task_context.task_index, actor_id)
+            else:
+                # This is a normal task.
+                task_id = TaskID.for_normal_task(self.current_job_id,
+                                                 self.current_task_id,
+                                                 self.task_context.task_index)
+
             task = ray._raylet.TaskSpec(
+                task_id,
                 job_id,
                 function_descriptor_list,
                 args_for_raylet,
@@ -1917,6 +1934,7 @@ def connect(node,
 
         function_descriptor = FunctionDescriptor.for_driver_task()
         driver_task_spec = ray._raylet.TaskSpec(
+            TaskID.for_driver_task(worker.current_job_id),
             worker.current_job_id,
             function_descriptor.get_function_descriptor_list(),
             [],  # arguments.