[Core] Actor handle refactoring (#8895)

* Marking needed changes.

* Resolve basic dependencies.

* In progress.

* linting.

* In progress 2.

* Linting.

* Refactor done. Cleanup needed.

* Linting.

* Recover kill actor in core worker because it is used inside raylet

* Cleanup.

* Use unique pointer instead. Unit tests are broken now.

* Fix the upstream change.

* Addressed code review 1.

* Lint.

* Addressed code review 2.

* Fix weird github history.

* Lint.

* Linting using clang 7.0.

* Use a better check message.

* Revert cpp stuff.

* Fix weird linting errors.

* Manuall fix all lint issues.

* Update a newline.

* Refactor some interface.

* Addressed all code review.

* Addressed code review

python/ray/_raylet.pxd

@@ -27,16 +27,16 @@ from ray.includes.function_descriptor cimport (
 )
 
 cdef extern from *:
-   """
-   #if __OPTIMIZE__ && __OPTIMIZE__ == 1
-   #undef __OPTIMIZE__
-   int __OPTIMIZE__ = 1;
-   #define __OPTIMIZE__ 1
-   #else
-   int __OPTIMIZE__ = 0;
-   #endif
-   """
-   int __OPTIMIZE__
+    """
+    #if __OPTIMIZE__ && __OPTIMIZE__ == 1
+    #undef __OPTIMIZE__
+    int __OPTIMIZE__ = 1;
+    #define __OPTIMIZE__ 1
+    #else
+    int __OPTIMIZE__ = 0;
+    #endif
+    """
+    int __OPTIMIZE__
 
 cdef extern from "Python.h":
     # Note(simon): This is used to configure asyncio actor stack size.
@@ -98,7 +98,7 @@ cdef class CoreWorker:
             self, worker, outputs, const c_vector[CObjectID] return_ids,
             c_vector[shared_ptr[CRayObject]] *returns)
     cdef yield_current_fiber(self, CFiberEvent &fiber_event)
-    cdef make_actor_handle(self, CActorHandle *c_actor_handle)
+    cdef make_actor_handle(self, const CActorHandle *c_actor_handle)
 
 cdef class FunctionDescriptor:
     cdef: