Updated material-branch to changes from master https://github.com/google/WebFundamentals/pull/1875

[johyphenel]

Merging changes from #1875 to material branch.

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[johyphenel]

CLA covered by Google corp - just signed individual one as well.

[googlebot]

CLAs look good, thanks!

[johyphenel]

@petele - should I be removing this markup from master?

[petele]

I manually merged this as #1880 because of other merging issues.