Add a jsaction.event.getTarget() function and use it in several places in jsaction/event.js.
Add a jsaction.event.getTarget() function and use it in several
places in jsaction/event.js.

A future CL will use this function in several places in Tactile code
to help make Tactile code run in IE8.
	Change on 2014/05/27 by eparker <eparker@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=68044672

google/jsaction,google/jsaction