New extension API: "tab.socketAddress"

chrome/common/extensions/api/extension_api.json

 [
   {
     "namespace": "extension",
     "unprivileged": true,
     "types": [
       {
         "id": "MessageSender",
         "type": "object",
         "description": "An object containing information about the script context that sent a message or request.",
         "properties": {
@@ skipping 903 matching lines @@
         "type": "object",
         "properties": {
           "id": {"type": "integer", "minimum": 0, "description": "The ID of the tab. Tab IDs are unique within a browser session."},
           "index": {"type": "integer", "minimum": 0, "description": "The zero-based index of the tab within its window."},
           "windowId": {"type": "integer", "minimum": 0, "description": "The ID of the window the tab is contained within."},
           "selected": {"type": "boolean", "description": "Whether the tab is selected."},
           "pinned": {"type": "boolean", "description": "Whether the tab is pinned."},
           "url": {"type": "string", "description": "The URL the tab is displaying."},
           "title": {"type": "string", "optional": true, "description": "The title of the tab. This may not be available if the tab is loading."},
           "favIconUrl": {"type": "string", "optional": true, "description": "The URL of the tab's favicon. This may not be available if the tab is loading."},
+          "socketAddress": {"type": "string", "optional": true, "description": "The 'IPv4:port' or '[IPv6]:port' endpoint of the socket that fetched this page. This may be omitted if the address is unknown."},
           "status": {"type": "string", "optional": true, "description": "Either <em>loading</em> or <em>complete</em>."},
           "incognito": {"type": "boolean", "description": "Whether the tab is in an incognito window."}
         }
       }
     ],
     "functions": [
       {
         "name": "get",
         "type": "function",
         "description": "Retrieves details about the specified tab.",
@@ skipping 3566 matching lines @@
                   "token": { "type": "string", "optional": true }
                 }
               }
             ]
           }
         ]
       }
     ]
   }
 ]