Add tests for platformstyle.js

[Jetshree]

Current Behavior

Currently platformstyle.js have 0% test coverage.

Desired Situation

Add tests to ensure the file is executed during test runs and coverage reflects the exercised code paths.

Checklist

• I have read and followed the project's code of conduct.
• I have searched for similar issues before creating this one.
• I have provided all the necessary information to understand and reproduce the issue.
• I am willing to contribute to the resolution of this issue.

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