be smarter when dealing with policy_json input

Now module will assume that if the argument is a string it is already formated as json
and will only try to convert non strings into json string.
Also removed unused 'msg' var declarations and the ifs that set them
fixes #2009

lib/ansible/modules/cloud/amazon/iam_policy.py

@@ -144,9 +144,7 @@ def user_action(module, iam, name, policy_name, skip, pdoc, state):
       if urllib.unquote(iam.get_user_policy(name, pol).
                         get_user_policy_result.policy_document) == pdoc:
         policy_match = True
-        if policy_match:
-          msg=("The policy document you specified already exists "
-               "under the name %s." % pol)
+
     if state == 'present' and skip:
       if policy_name not in current_policies and not policy_match:
         changed = True
@@ -187,15 +185,12 @@ def role_action(module, iam, name, policy_name, skip, pdoc, state):
       module.exit_json(changed=False)
     else:
       module.fail_json(msg=e.message)
-      
-  try:    
+
+  try:
     for pol in current_policies:
       if urllib.unquote(iam.get_role_policy(name, pol).
                         get_role_policy_result.policy_document) == pdoc:
         policy_match = True
-        if policy_match:
-          msg=("The policy document you specified already exists "
-               "under the name %s." % pol)
     if state == 'present' and skip:
       if policy_name not in current_policies and not policy_match:
         changed = True
@@ -303,10 +298,12 @@ def main():
           pdoc = json.dumps(json.load(json_data))
           json_data.close()
   elif module.params.get('policy_json') != None:
-      try:
-        pdoc = json.dumps(module.params.get('policy_json'))
-      except Exception as e:
-        module.fail_json(msg=str(e) + '\n' + module.params.get('policy_json'))
+      # if its a string, assume it is already JSON
+      if not isinstance(pdoc, basestring):
+        try:
+          pdoc = json.dumps(module.params.get('policy_json'))
+        except Exception as e:
+          module.fail_json(msg='Failed to convert the policy into valid JSON: %s' % str(e))
   else:
     pdoc=None