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- This CL expands on the dynamic form filling logic by tracking the filling
context for multiple forms, therefore allowing multiple dynamic forms on
the same page to get filled, e.g., billing and shipping address forms on
victoriassecret.com
_ It also fixes a bug where previously filled fields were not being
refilled even if their value was reset during the dynamic form change.
- It also rewrites the JS logic in the test html files to eliminate race
conditions and improve readability.

Change-Id: I44681742820d5285e77a4e9e4a61917ae4bfc41e
Reviewed-on: https://chromium-review.googlesource.com/1003381Reviewed-by: Sebastien Seguin-Gagnon <sebsg@chromium.org>
Commit-Queue: Moe Ahmadi <mahmadi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550183}