This pull request was opened against a branch other than master. Since Flutter pull requests should not normally be opened against branches other than master, I have changed the base to master. If this was intended, you may modify the base back to flutter-1.18-candidate.11. See the Release Process for information about how other branches get updated.

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/cc @dnfield

All (the pull request submitter and all commit authors) CLAs are signed, but one or more commits were authored or co-authored by someone other than the pull request submitter.

We need to confirm that all authors are ok with their commits being contributed to this project. Please have them confirm that by leaving a comment that contains only @googlebot I consent. in this pull request.

Note to project maintainer: There may be cases where the author cannot leave a comment, or the comment is not properly detected as consent. In those cases, you can manually confirm consent of the commit author(s), and set the cla label to yes (if enabled on your project).

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Is this ready for review?

pending flutter/engine#18317

@chenglu can you ack that you're okay with cherrypicking your change here? thank you!

thanks @chenglu I think you need to add a comment that says "@googlebot I consent."

@googlebot I consent.

CLAs look good, thanks!

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