Add name sources to Accessibility sidebar pane.

BUG=509893

Committed: https://crrev.com/3a7eea96258643de91f9800d1dabafca0560c347
Cr-Commit-Position: refs/heads/master@{#352966}

Review URL: https://codereview.chromium.org/1378483002

Cr-Commit-Position: refs/heads/master@{#353190}
16 files changed