Skip empty video chunks in writeVideoFrame

[flotwig]

No users have run into this, but video recording can fail in writeVideoFrame and crash the process if an empty video chunk is received. This only seems to happen if there's some other error recording the video, but that will be caught later on, so this patch prevents errors with video recording from crashing the process immediately by skipping empty video chunks altogether.

[cypress-bot]

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[cypress]

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Test summary

7018 • 0 • 98 • 0

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Run details

Project	cypress
Status	Passed
Commit	32e0a26
Started	Mar 24, 2020 2:24 PM
Ended	Mar 24, 2020 2:32 PM
Duration	07:41 💡
OS	Linux Debian - 10.1
Browser	Multiple

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[brian-mann]

• Can you write a single unit test for this? Otherwise this guard may get lost at some point.
• Also can you add a note above the conditional explaining why this is important. The context is lost unless you read the comments.

[brian-mann]

there's a packages/fs you could use... but it will yell at you for using *sync methods

[cypress-bot]

Released in 4.3.0.

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