Update references to the extension messaging APIs to point to the "runtime"

chrome/common/extensions/api/context_menus.json

Index: chrome/common/extensions/api/context_menus.json
diff --git a/chrome/common/extensions/api/context_menus.json b/chrome/common/extensions/api/context_menus.json
index c4113ea7a4374dc08905ad7f736812e9dba8d285..5f37e877056c80ab7fb27c683bc56d86700d8589 100644
--- a/chrome/common/extensions/api/context_menus.json
+++ b/chrome/common/extensions/api/context_menus.json
@@ -78,7 +78,7 @@
       {
         "name": "create",
         "type": "function",
-        "description": "Creates a new context menu item. Note that if an error occurs during creation, you may not find out until the creation callback fires (the details will be in chrome.extension.lastError).",
+        "description": "Creates a new context menu item. Note that if an error occurs during creation, you may not find out until the creation callback fires (the details will be in chrome.runtime.lastError).",
         "returns": {
           "choices": [
             { "type": "integer" },
@@ -170,7 +170,7 @@
             "type": "function",
             "name": "callback",
             "optional": true,
-            "description": "Called when the item has been created in the browser. If there were any problems creating the item, details will be available in chrome.extension.lastError.",
+            "description": "Called when the item has been created in the browser. If there were any problems creating the item, details will be available in chrome.runtime.lastError.",
             "parameters": []
           }
         ]