* fix: cpplint didn't work in GN
* feat: make cpplint non-errors less noisy
* refactor: remove unneeded findCppLint helper
We don't need this in the GN world: it's the user's responsibility
to have depot_tools in their path.
* refactor: use const instead of let where possible
* refactor: port the cpplint runner to javascript
* fix: address code review suggestions
* refactor: make .cc, bootstrapped test funcs inline
* refactor: make CC_ROOTS inline too
* fix: test process.mainModule before calling main()
* refactor: reverse logic order in findChangedFiles
* refactor: make findChangedFiles() more readable
* fix: copy-paste error introduced in 3b17400
* chore: fix grammar in log message
