Make output placeholders like json.output index-able by name.

recipe_modules/json/example.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 DEPS = [
   'json',
   'path',
   'python',
   'raw_io',
   'step',
@@ skipping 19 matching lines @@
   result = api.python.inline(
       'foo',
       """
       import json
       import sys
       with open(sys.argv[1], 'w') as f:
         f.write(json.dumps([1, 2, 3]))
       with open(sys.argv[2], 'w') as f:
         f.write(json.dumps(['x', 'y', %s]))
       """ % repr(FULLWIDTH_Z),
-      args=[api.json.output(), api.json.output()],
+      args=[api.json.output(name='1'), api.json.output(name='2')],
   )
-  assert result.json.output_all == [[1, 2, 3], ['x', 'y', FULLWIDTH_Z]]
+  assert result.json.outputs['1'] == [1, 2, 3]
+  assert result.json.outputs['2'] == ['x', 'y', FULLWIDTH_Z]
 
   example_dict = {'x': 1, 'y': 2}
 
   # json.input(json_data) expands to a path containing that rendered json
   step_result = api.step('json through',
     ['cat', api.json.input(example_dict)],
     stdout=api.json.output(),
     step_test_data=lambda: api.json.test_api.output_stream(example_dict))
   assert step_result.stdout == example_dict
 
   # json.read reads a file containing json data.
   leak_path = api.path['slave_build'].join('temp.json')
   api.step('write json to file',
     ['cat', api.json.input(example_dict)],
     stdout=api.raw_io.output(leak_to=leak_path))
   step_result = api.json.read(
       'read json from file we just wrote', leak_path,
       step_test_data=lambda: api.json.test_api.output(example_dict))
   assert step_result.json.output == example_dict
 
 
 def GenTests(api):
   yield (api.test('basic') +
       api.step_data('echo1', stdout=api.json.output([1, 2, 3])) +
       api.step_data(
           'foo',
-          api.json.output([1, 2, 3]) +
-          api.json.output(['x', 'y', FULLWIDTH_Z]),
+          api.json.output([1, 2, 3], name='1') +
+          api.json.output(['x', 'y', FULLWIDTH_Z], name='2'),
       ))