commit c9df91f8cc501a4a952eb08877c3c3e6b2ca01bb
author tkent <tkent@chromium.org> Thu Jul 07 16:22:51 2016
committer Commit bot <commit-bot@chromium.org> Thu Jul 07 16:25:13 2016
tree 74882aa7bbbc60947d637c8dabeae5340436265b
parent df31fc35cd09645097cac15e84ff8a2173c644fb

SELECT element: Improve performance of HTMLSelectElement::optionIndexToBeShown().

It was usually O(N).  This CL makes it O(1) by changing the return value from
index to HTMLOptionElement*, and renames it to optionToBeShown().

Also,
 - Change the argument type of LayoutMenuList::didSetSelectionIndex and
   didUpdateActiveOption; index -> HTMLOptionElement*.
 - Rename didSetSelectionIndex to didSelectOption.
 - Merge LayoutMenuList::setTextFromOption into updateFromElement.

BUG=577989

Review-Url: https://codereview.chromium.org/2126023005
Cr-Commit-Position: refs/heads/master@{#404157}