Sessions API - previously Session Restore API. Supports restoring currently open foreign windows an…

chrome/common/extensions/api/tabs.json

Index: chrome/common/extensions/api/tabs.json
diff --git a/chrome/common/extensions/api/tabs.json b/chrome/common/extensions/api/tabs.json
index c18f5c45cac9db29cc551d4e264ffc365a4d5164..70b803321bca851d6d94c08cb2829324be27a8c6 100644
--- a/chrome/common/extensions/api/tabs.json
+++ b/chrome/common/extensions/api/tabs.json
@@ -11,7 +11,7 @@
         "id": "Tab",
         "type": "object",
         "properties": {
-          "id": {"type": "integer", "minimum": 0, "description": "The ID of the tab. Tab IDs are unique within a browser session."},
+          "id": {"type": "integer", "minimum": 0, "optional": true, "description": "The ID of the tab. Tab IDs are unique within a browser session. Under some circumstances a Tab may not be assigned an ID, for example when querying foreign tabs from the $ref:sessions API, in which case sessionId may be present."},
           // TODO(kalman): Investigate how this is ending up as -1 (based on window type? a bug?) and whether it should be optional instead.
           "index": {"type": "integer", "minimum": -1, "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."},
@@ -24,7 +24,8 @@
           "title": {"type": "string", "optional": true, "optional": true, "description": "The title of the tab. This will only be present if the extension has the 'tabs' or 'webNavigation' permission. It may also be an empty string if the tab is loading."},
           "favIconUrl": {"type": "string", "optional": true, "optional": true, "description": "The URL of the tab's favicon. This will only be present if the extension has the 'tabs' or 'webNavigation' permission. It may also be an empty string if the tab is loading."},
           "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."}
+          "incognito": {"type": "boolean", "description": "Whether the tab is in an incognito window."},
+          "sessionId": {"type": "string", "optional": true, "description": "The session ID used to uniquely identify a Tab from the $ref:sessions API."}
         }
       },
       {