static/frontend: add escape keydown to close details dialog

[essjay05]

Updates the main script files to implement the ability of using the
escape keydown to close the details tooltip if it's open.

Fixes b/283533035

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[gopherbot]

Message from Gopher Robot:

Patch Set 1:

(1 comment)

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[gopherbot]

Message from Jonathan Amsterdam:

Patch Set 1:

(1 comment)

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[gopherbot]

Message from Joy Serquina (xWF):

Patch Set 3:

(1 comment)

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[gopherbot]

This PR (HEAD: 4a94647) has been imported to Gerrit for code review.

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[essjay05]

Closing in favor of updated/working PR: #104