Adds actual logic to allow goog.events to delegate to
goog.events.Listenable when appropriate.

R=nicksantos,gboyer
DELTA=218 (191 added, 4 deleted, 23 changed)


Revision created by MOE tool push_codebase.
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git-svn-id: http://closure-library.googlecode.com/svn/trunk@2468 0b95b8e8-c90f-11de-9d4f-f947ee5921c8
Ensure that unlisten/unlistenByKey does not fail when called
on disposed EventTarget. This turns out to be pretty common
when you have a disposed event target stored in an
EventHandler.

R=nicksantos
DELTA=21 (17 added, 4 deleted, 0 changed)


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git-svn-id: http://closure-library.googlecode.com/svn/trunk@2469 0b95b8e8-c90f-11de-9d4f-f947ee5921c8
Return value of goog.events and goog.events.listenOnce is going to
change from ?number to goog.events.ListenableKey. As a first step, we
are switching the return value to a typedef goog.events.Key (currently
just typedef to ?number). This CL switches JS files to use this typedef.

Obviously, the subsequent change will be problematic if this code
make an assumption that the return value is a number and uses the return
value in context where the number is required (e.g. goog.isNumber, using
it as index to an array). While I've tried my best to fix these usages,
I may have missed some of them. Please check that the code will still
remain correct if the return value of goog.events.listen/listenOnce is
changed to an object (goog.events.ListenableKey). Furthermore, if
you know of any other location where the return value is used in a context
that require it to be numbers, please send me a quick email.

R=davec
DELTA=3 (0 added, 0 deleted, 3 changed)


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git-svn-id: http://closure-library.googlecode.com/svn/trunk@2470 0b95b8e8-c90f-11de-9d4f-f947ee5921c8
Deprecate goog.dom.a11y.

R=chrishenry,nnaze,ruilopes
DELTA=28 (24 added, 4 deleted, 0 changed)


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git-svn-id: http://closure-library.googlecode.com/svn/trunk@2471 0b95b8e8-c90f-11de-9d4f-f947ee5921c8