Merge pull request ampproject#2262 from cramforce/timeout-message

Always log when channel with parent cannot be established.

Merge tag '1456286053779' into release

Merge pull request ampproject#2253 from dvoytenko/fixes51

Extend messaging channel timeout to 20s

Merge tag '1456275888387' into release

Merge pull request ampproject#2246 from dvoytenko/access48

Fix for Base CID read too early

Merge pull request ampproject#2231 from dvoytenko/fixed4

Border-top for iOS/embedded case

Merge tag '1456190436339' into release

Merge pull request ampproject#2210 from dvoytenko/fixed3

Use FixedLayer for user notifications

Merge tag '1456166258978' into release

Merge pull request ampproject#2199 from ampproject/cramforce-patch-1

Work around for encoding problem with adobe analytics.