Remove legacy Ray code. (#3121)

* Remove legacy Ray code.

* Fix cmake and simplify monitor.

* Fix linting

* Updates

* Fix

* Implement some methods.

* Remove more plasma manager references.

* Fix

* Linting

* Fix

* Fix

* Make sure class IDs are strings.

* Some path fixes

* Fix

* Path fixes and update arrow

* Fixes.

* linting

* Fixes

* Java fixes

* Some java fixes

* TaskLanguage -> Language

* Minor

* Fix python test and remove unused method signature.

* Fix java tests

* Fix jenkins tests

* Remove commented out code.

python/ray/tune/ray_trial_executor.py

@@ -213,20 +213,9 @@ class RayTrialExecutor(TrialExecutor):
         assert self._committed_resources.gpu >= 0
 
     def _update_avail_resources(self):
-        if ray.worker.global_worker.use_raylet:
-            # TODO(rliaw): Remove once raylet flag is swapped
-            resources = ray.global_state.cluster_resources()
-            num_cpus = resources["CPU"]
-            num_gpus = resources["GPU"]
-        else:
-            clients = ray.global_state.client_table()
-            local_schedulers = [
-                entry for client in clients.values() for entry in client
-                if (entry['ClientType'] == 'local_scheduler'
-                    and not entry['Deleted'])
-            ]
-            num_cpus = sum(ls['CPU'] for ls in local_schedulers)
-            num_gpus = sum(ls.get('GPU', 0) for ls in local_schedulers)
+        resources = ray.global_state.cluster_resources()
+        num_cpus = resources["CPU"]
+        num_gpus = resources["GPU"]
         self._avail_resources = Resources(int(num_cpus), int(num_gpus))
         self._resources_initialized = True