Revert "Merge pull request #14138 from malini/mixin"

This reverts commit 091161997bebfc0c2d053339b1c9891c57216920, reversing
changes made to 50c75716ce9740ac1443e02140ae85b4885d47c5.
Merge pull request #14424 from malini/master

Revert "Merge pull request #14138 from malini/mixin"