added issue reference to todos

[vendz]

in reference to #2119

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[vendz]

@googlebot I signed it!

[vendz]

@kwalrath please review my PR

[kwalrath]

Thank you, @vendz!

I believe that the test failures are due to line length > 80. Could you break up the lines? While you're at it, you might make these full URLs. Or not. :)

[vendz]

@kwalrath I have made changes to the TODO line so if you could review my PR now

[vendz]

@parlough i have made the changes you requested in this PR itself so if you could review it

[parlough]

Some minor suggestions, feel free to ignore them if desired.

Thanks again!

[parlough]

Can you remove this one instead like mentioned in #3297 and include Fixes #3297 again?

Suggested change

	// TODO(miquelbeltran) language-tour.md should explain that
	// non-required params can be null (#3297)

[parlough]

Can you place it after the whole comment and instead put a link to the issue so its easier to access when navigating the source?

Suggested change

	// TODO(chalin): I believe that handleError's test argument should be declared (#3298)
	// as follows, but it isn't: {bool Function(dynamic error) test}.
	// TODO(chalin): I believe that handleError's test argument should be declared
	// as follows, but it isn't: {bool Function(dynamic error) test}.
	// (https://github.com/dart-lang/site-www/issues/3298)

[vendz]

@parlough made the changes you requested.

[parlough]

@vendz Thanks for all the work, looks good to me! I'm running the checks and if they're all green, I'll merge these changes :)

[parlough]

All tests were green after I removed the extra whitespace and the changes have been committed to the main branch(c95f9bb). Thanks again @vendz and good work and communication around your first contribution on site-www :D