Fix a bug of sequential focus navigation with <select multiple>, and so on.

<select multiple>, <select size=2-or-greater>, and <input
type=date/datetime-local/month/time/week> had a bug that they prevented
sequential focus navigation even if they were not focusabble.

Change nextNodeWithGreaterTabIndex() so that it uses adjustedTabIndex().

BUG=425937
TEST=automated

Review URL: https://codereview.chromium.org/681103003

git-svn-id: svn://svn.chromium.org/blink/trunk@184877 bbb929c8-8fbe-4397-9dbb-9b2b20218538