Add onChanged callback for chrome.sessions API.

chrome/common/extensions/api/sessions.json

Index: chrome/common/extensions/api/sessions.json
diff --git a/chrome/common/extensions/api/sessions.json b/chrome/common/extensions/api/sessions.json
index a063d920b450c6b7f26af0f4f919b1aa68dc3616..6cffa173dde9c606f2ee0d1d890dffc8da529335 100644
--- a/chrome/common/extensions/api/sessions.json
+++ b/chrome/common/extensions/api/sessions.json
@@ -107,6 +107,13 @@
         ]
       }
     ],
+    "events": [

[not at google - send to devlin, 2014/03/17 14:21:18]

Cool, we've wanted to add this sort of functionality for a while.

We will probably want to include some data about the sessions which changed in
here.

However, I can't find a reference to a proposal for this API. Typically you
would fill out the API proposal on that page (it's a public document) explaining
the use case for this method and so on.

A number of the questions won't apply to you but the most important part is
proposing the new event.

[wjywbs, 2014/03/17 19:27:24]

Sure, I will write the proposal tonight.

[not at google - send to devlin, 2014/03/19 16:22:41]

Ok, let's resolve my comments in there. Then ping this CL to me again.

+      {
+        "name": "onRecentlyClosed",
+        "description": "Fired when recently closed tabs and/or windows are changed.",
+        "type": "function"
+      }
+    ],
     "properties": {
       "MAX_SESSION_RESULTS": {
         "value": 25,