Allow screen-reader to identify the alert errors. Fixes#4763
Added role alertdialog for confirm and alert dialog.
Added role status for all status bars/banners.
Added role alert for error bars.
Added aria-labelledby for charts on each dashboard.
Added tabindex for each chart so that it is navigable using tab key.
2) Fixed minor issue where we use dialog tab navigator keyboard shortcut only on visible tabs.
3) Fixed an issue where Zoom in, Zoom out, Zoom to original and Download button should not blur the focus after a click on them.
Initial patch sent by Murtuza Zabuawala.
1) Dashboard -> Server Activity grid: terminate the session, cancel active button not navigable using tab key.
2) SQL -> If the focus inside code mirror control tab navigation not working.
Fixes#4930