Test passes in Zend PHP, but fails in HHVM.

PHPUnit 4.1.3 by Sebastian Bergmann.

Configuration read from /srv/mediawiki/tests/phpunit/suite.xml

............................................................... 63 / 193 ( 32%)
............................................................... 126 / 193 ( 65%)
.................................................E

Time: 1.12 seconds, Memory: 21.39Mb

There was 1 error:

1. TemplateDataBlobTest::testGetDataInLanguage with data set #7 (array('{

					"params": {
						"foo": {}
					},
					"sets": [
						{
							"label": {
								"es": "Spanish",
								"de": "German"
							},
							"params": ["foo"]
						}
					]
				}
				', '{
					"description": null,
					"params": {
						"foo": {
							"label": null,
							"required": false,
							"suggested": false,
							"description": null,
							"deprecated": false,
							"aliases": [],
							"default": "",
							"type": "unknown"
						}
					},
					"paramOrder": ["foo"],
					"sets": [
						{
							"label": "Spanish",
							"params": ["foo"]
						}
					]
				}
				', 'fr', 'Set label is not optional, choose first available key as final fallback'))

Invalid operand type was used: expecting an array

/srv/mediawiki/extensions/TemplateData/TemplateDataBlob.php:522
/srv/mediawiki/extensions/TemplateData/tests/TemplateDataBlobTest.php:684
/srv/mediawiki/tests/phpunit/MediaWikiTestCase.php:133
/srv/mediawiki/tests/phpunit/MediaWikiPHPUnitCommand.php:42

FAILURES!
Tests: 176, Assertions: 577, Errors: 1.

Version: master
Severity: normal