Syncing script's configuration duplicates a lot of boilerplate

Syncing script's configuration duplicates a lot of boilerplate
https://bugs.webkit.org/show_bug.cgi?id=160574

Rubber-stamped by Chris Dumez.

This patch makes each configuration accept an array of platforms and types so that we can write:

{"type": "speedometer", "builder": "mba", "platform": "Trunk El Capitan MacBookAir"},
{"type": "speedometer", "builder": "mbp", "platform": "Trunk El Capitan MacBookPro"},
{"type": "speedometer", "builder": "mba", "platform": "Trunk Sierra MacBookAir"},
{"type": "speedometer", "builder": "mbp", "platform": "Trunk Sierra MacBookPro"},
{"type": "jetstream", "builder": "mba", "platform": "Trunk El Capitan MacBookAir"},
{"type": "jetstream", "builder": "mbp", "platform": "Trunk El Capitan MacBookPro"},
{"type": "jetstream", "builder": "mba", "platform": "Trunk Sierra MacBookAir"},
{"type": "jetstream", "builder": "mbp", "platform": "Trunk Sierra MacBookPro"},

more concisely as:

{"builder": "mba", "types": ["speedometer", "jetstream"],
    "platforms": ["Trunk El Capitan MacBookAir", "Trunk Sierra MacBookAir"]},
{"builder": "mbp", "types": ["speedometer", "jetstream"],
    "platforms": ["Trunk El Capitan MacBookPro", "Trunk Sierra MacBookPro"]},

* tools/js/buildbot-syncer.js:
(BuildbotSyncer._loadConfig):
(BuildbotSyncer._expandTypesAndPlatforms): Added. Clones a new configuration entry for each type
and platform.
(BuildbotSyncer._createTestConfiguration): Extracted from _loadConfig.
(BuildbotSyncer._validateAndMergeConfig): Added a new argument that specifies a property that
shouldn't be merged into the configuration. Also added the support for 'types' and 'platforms',
and merged the code for verify an array of strings. Finally, allow the appearance of 'properties'
since this function can now be called on a cloned configuration in which 'arguments' had already
been renamed to 'properties'.

* unit-tests/buildbot-syncer-tests.js: Added a test case to parse a consolidated configuration.
(sampleiOSConfigWithExpansions): Added.

* unit-tests/resources/mock-v3-models.js:
(MockModels.inject): Added a few more mock models for the newly added test.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@204151 268f45cc-cd09-0410-ab3c-d52691b4dbfc