add guards support in JavascriptParser #6011

Job	Run time
lint	2m 4s
unit	1m 9s
basic	1m 28s
validate-legacy-node	9s
integration (ubuntu-latest, 10.x, a)	8m 34s
integration (ubuntu-latest, 10.x, b)	9m 9s
integration (ubuntu-latest, 20.x, a)	7m 9s
integration (ubuntu-latest, 20.x, b)	8m 15s
integration (windows-latest, 10.x, a)	12m 39s
integration (windows-latest, 10.x, b)	12m 59s
integration (windows-latest, 20.x, a)	10m 24s
integration (windows-latest, 20.x, b)	10m 34s
integration (macos-latest, 10.x, a)	11m 30s
integration (macos-latest, 10.x, b)	26m 32s
integration (macos-latest, 20.x, a)	21m 50s
integration (macos-latest, 20.x, b)	9m 32s
integration (ubuntu-latest, lts/*, a, 1)	7m 11s
integration (ubuntu-latest, lts/*, b, 1)	8m 20s
integration (ubuntu-latest, 21.x, a)	7m 31s
integration (ubuntu-latest, 21.x, b)	8m 23s
integration (ubuntu-latest, 18.x, a)	7m 21s
integration (ubuntu-latest, 18.x, b)	8m 40s
integration (ubuntu-latest, 16.x, a)	7m 58s
integration (ubuntu-latest, 14.x, a)	8m 10s
integration (ubuntu-latest, 12.x, a)	7m 46s
	3h 45m 17s

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