Merge pull request #261 from danleh/dotnet-mime-fix #813

Job	Run time
Test Build	26s
Test Browser on macOS (safari, disabled)	1m 55s
Test Browser on Linux (chrome, default)	1m 7s
Test Browser on macOS (safari, default)	1m 49s
Test Browser on macOS (safari, main)	54s
Test Browser on Linux (firefox, main)	1m 0s
Test Browser on Linux (chrome, main)	26s
Test Browser on Linux (firefox, disabled)	1m 15s
Test Browser on Linux (firefox, default)	2m 4s
Test Shell (spidermonkey, default)	5m 15s
Test Browser on Linux (chrome, disabled)	1m 3s
Test Shell (spidermonkey, disabled)	2m 0s
Test Shell (jsc, main)	51s
Test Shell (jsc, default)	3m 8s
Test Shell (v8, default)	2m 40s
Test Shell (v8, main)	40s
Test Shell (v8, disabled)	1m 35s
Test Shell (jsc, disabled)	1m 49s
Test Shell (spidermonkey, main)	48s
	30m 45s

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