Improve documentation for the management.setEnabled function
Improve documentation for the management.setEnabled function

Added some information about:
-user gesture requirement
-native confirmation UI

BUG=178319

Review URL: https://codereview.chromium.org/1649803002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#372143}

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