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Updated the tests. PTAL.

/tmp/flutter sdk/packages/flutter_tools/lib/src/web/chrome.dart:330: trailing U+0009 tab character
/tmp/flutter sdk/packages/flutter_tools/lib/src/web/chrome.dart:331: trailing U+0009 tab character
/tmp/flutter sdk/packages/flutter_tools/lib/src/web/chrome.dart:332: trailing U+0009 tab character
/tmp/flutter sdk/packages/flutter_tools/lib/src/web/chrome.dart:333: trailing U+0009 tab character
/tmp/flutter sdk/packages/flutter_tools/lib/src/web/chrome.dart:334: trailing U+0009 tab character
/tmp/flutter sdk/packages/flutter_tools/lib/src/web/chrome.dart:335: trailing U+0009 tab character
/tmp/flutter sdk/packages/flutter_tools/test/general.shard/web/chrome_test.dart:233: trailing U+0020 space character

nit: you need to remove the trailing whitespace

I'm assuming this doesn't have the same issues that made @jonahwilliams change it to a new random profile on every run. But it's not clear to me how. Could someone help me understand?

Chrome must be provided a custom user-data-dir to enable the remote debug port. If you reuse a data dir, Chrome will potentially "attach" to an existing Chrome instance and the remote debug port may silently fail. I believe that's what @jonahwilliams was trying to resolve. As far as I can tell, since we use a different data dir, Chrome will not "attach" to any existing instance and we won't run into debugging issues.