remove partial dependency job id logic

* Late in the release we added job dependency tracking to the DB. We
decided not to use this information in the scheduler. However, I
half-ass added code to the scheduler to use it. Note that we still
determine inv and job update dependency by using a hack of the related
creation time, job.created-2 and job.created-1 respectively.

This removes any use of job dependent id expect for purposes of chain
failing.

awx/main/scheduler/partial.py

@@ -1,7 +1,6 @@
 
 # Python
 import json
-import itertools
 
 # AWX
 from awx.main.utils import decrypt_field_value
@@ -62,35 +61,13 @@ class PartialModelDict(object):
     def task_impact(self):
         raise RuntimeError("Inherit and implement me")
 
-    @classmethod
-    def merge_values(cls, values):
-        grouped_results = itertools.groupby(values, key=lambda value: value['id'])
-
-        merged_values = []
-        for k, g in grouped_results:
-            groups = list(g)
-            merged_value = {}
-            for group in groups:
-                for key, val in group.iteritems():
-                    if not merged_value.get(key):
-                        merged_value[key] = val
-                    elif val != merged_value[key]:
-                        if isinstance(merged_value[key], list):
-                            if val not in merged_value[key]:
-                                merged_value[key].append(val)
-                        else:
-                            old_val = merged_value[key]
-                            merged_value[key] = [old_val, val]
-            merged_values.append(merged_value)
-        return merged_values
-
 
 class JobDict(PartialModelDict):
     FIELDS = (
         'id', 'status', 'job_template_id', 'inventory_id', 'project_id', 
         'launch_type', 'limit', 'allow_simultaneous', 'created', 
         'job_type', 'celery_task_id', 'project__scm_update_on_launch',
-        'forks', 'start_args', 'dependent_jobs__id',
+        'forks', 'start_args',
     )
     model = Job
 
@@ -113,8 +90,7 @@ class JobDict(PartialModelDict):
         kv = {
             'status__in': status
         }
-        merged = PartialModelDict.merge_values(cls.model.objects.filter(**kv).values(*cls.get_db_values()))
-        return [cls(o) for o in merged]
+        return [cls(o) for o in cls.model.objects.filter(**kv).values(*cls.get_db_values())]
 
 
 class ProjectUpdateDict(PartialModelDict):