refactor(@angular-devkit/schematics): initial isolated declarations t… #630

Job	Run time
list	30s
workflow (devkit-core-tests)	30s
workflow (build-cli)	31s
workflow (build-unit-tests)	37s
workflow (modules-builder-tests)	39s
workflow (devkit-core-tests-rerun)	40s
	3m 27s

Provide feedback