commit 58d8c299b23fad86a6fe7e2b489f9cdded704011
author Michael Liao (WPT) <michael.liao@microsoft.com> Tue Jul 16 23:19:40 2019
committer Commit Bot <commit-bot@chromium.org> Tue Jul 16 23:19:40 2019
tree bfa90cf69515795c56512a90b191e316417c52c2
parent 9d3975b39ee3cae2557432b5d48afa092d8da1fe

DevTools: removing header 2 tag from EmptyWidget and BackgroundServiceView

Reason:
- EmptyWidget elements should not be headers as they do not meet the criteria (https://www.w3.org/TR/WCAG20-TECHS/G141.html)
- Marking a non-header as a header will impede SR accessibility for the affected tools

Changes:
- Replacing <h2> tag from UI.EmptyWidget with <div>
- Removing <h2> tag from _showPreview(...) function with <div> in BackgroundServiceView.js (supposed to mimic UI.EmptyWidget element)
- Adding 'empty-bold-text' css in emptyWidget.css that mimics <h2> styling and adding the class to the <div> tags to retain h2 styling

Examples of UI.EmptyWidget use cases:
https://imgur.com/a/qpJeB2Y

BackgroundServiceView.js unique case:
https://imgur.com/cAW8Nu0

Change-Id: Iff3356f12b3dd1906141de4cfe9980b7b1d9c929
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1693808
Reviewed-by: Joel Einbinder <einbinder@chromium.org>
Commit-Queue: Michael Liao <michael.liao@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#678026}