Treat byte slices as binary blobs in Any

[ansel1]

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[mention-bot]

@ansel1, thanks for your PR! By analyzing the history of the files in this pull request, we identified @akshayjshah, @prashantv and @pravj to be potential reviewers.

[CLAassistant]

All committers have signed the CLA.

[akshayjshah]

Looks great! I'm going to push a commit to change the docs a bit and then land.