keyboard support on geo/charting does not show tooltips

[mikeb]

The keyboard support for the geo maps does not display the tooltips properly. See ​http://archive.dojotoolkit.org/nightly/checkout/dojox/geo/charting/tests/test_maps.html as an example; when you move around with the keyboard, the states are highlighted but the tooltips do not appear. This also causes the markerText to not be spoken by Jaws.

The attached patch causes the tooltip to display when using the mouse. Since the tooltips have role=alert, they are announced by the screen reader.

[cjolif]

There is I think a slightly better solution which is to not have the onclickhandler call raising exceptions when the event is null. I have implemented it. Commmit is coming in 1 minute. It should fix the problem equally but please double check.

[cjolif]

In [28203]:

fixes #15051. Avoid onclickhandler to crash when navigating the map using keyboard thus allowing tooltips to be diplayed (+other small cleanups)

[cjolif]

In [28204]:

fixes #15051. Backport the fix to 1.7.