refactor: reduce code duplication in FloodFill

[vil02]

know more

Describe your change:

This PR reduced the code duplication and adds missing tests.

Checklist:

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized.
• I know that pull requests will not be merged if they fail the automated tests.
• This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
• All new JavaScript files are placed inside an existing directory.
• All filenames should use the UpperCamelCase (PascalCase) style. There should be no spaces in filenames.
  Example:UserProfile.js is allowed but userprofile.js,Userprofile.js,user-Profile.js,userProfile.js are not
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• If this pull request resolves one or more open issues then the commit message contains Fixes: #{$ISSUE_NO}.

[appgurueu]

You could also consider making checkLocation return a boolean - it could return whether the location is valid.

Then you'd be duplicating the two throws (but this is actually not that bad, because such side effects being "hidden" in a function may be a bit surprising).

You would then be able to deduplicate the x >= 0 && x < rgbData.length && y >= 0 && y < rgbData[0].length bounds check as well.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.08%. Comparing base (bd34e9f) to head (1be1853).

Additional details and impacted files

@@ Coverage Diff @@## master #1645 +/- ## ========================================== + Coverage 84.07% 84.08% +0.01%  ========================================== Files 375 375 Lines 19688 19685 -3 Branches 2913 2917 +4 ========================================== + Hits 16552 16553 +1 + Misses 3136 3132 -4 

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[vil02]

@appgurueu thanks for 1be1853.

[appgurueu]

Ah, I forgot to approve, didn't I...