Handle test failure better (5.1)

[thomasneirynck]

DO NOT MERGE!

This is the same change as #9251, but targeting 5.1.

There have been intermittent failures in CI. This should give us a more meaningful error should they occur again.

[thomasneirynck]

jenkins, test this

[thomasneirynck]

jenkins, test this

[thomasneirynck]

jenkins, test this

[thomasneirynck]

jenkins, test this

[thomasneirynck]

jenkins, test this

[thomasneirynck]

jenkins, test this

[thomasneirynck]

jenkins, test this

[thomasneirynck]

jenkins, test this

[thomasneirynck]

failure: https://kibana-ci.elastic.co/job/elastic+kibana+pull-request+multijob-intake/2266/console

error is identical to failures in 5.x (#9255 (comment))

Chrome 54.0.2840 (Linux 0.0.0) tag cloud should position elements correctly: 0 FAILED
	Error: top boundary of tag should have been inside | bbox-of-tag: [1161.5,1300,1170.5,1313] vs
	     bbox-of-container: 512,512
	    at verifyBbox (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:350333:14)
	    at isInsideContainer (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:350325:6)
	    at http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:350319:8
	    at Array.forEach (native)
	    at verifyTagProperties (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:350308:21)
	    at TagCloud.onRender (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:350073:12)
	    at TagCloud.EventEmitter.emit (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:242809:18)
	    at TagCloud._processQueue (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:241962:15)
	    at resolveWhenDone (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:242050:18)
	    at SVGTextElement.<anonymous> (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:242065:10)
	    at SVGTextElement.event (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:181696:43)
	    at Object.tick [as c] (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:190110:55)
	    at d3_timer_mark (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:183352:74)
	    at d3_timer_step (http://localhost:5610/bundles/tests.bundle.js?shards=4&shard_num=4:183332:16)

[thomasneirynck]

jenkins, test this

[thomasneirynck]

jenkins, test this

[thomasneirynck]

failure: https://kibana-ci.elastic.co/job/elastic+kibana+pull-request+multijob-intake/2277/console

[thomasneirynck]

jenkins, test this

[thomasneirynck]

closing, was able to reproduce error in CI. errors are identical between all branches (5.1, 5.1, master)