Don't send the oncompleted signal twice in the webnavigation API

chrome/test/data/extensions/api_test/webnavigation/test_history.js

Index: chrome/test/data/extensions/api_test/webnavigation/test_history.js
diff --git a/chrome/test/data/extensions/api_test/webnavigation/test_history.js b/chrome/test/data/extensions/api_test/webnavigation/test_history.js
index 409aec036b6414cf402f425dd9a215cb08e1d45d..fedc5f5ba92f7fcc61d152957f376261a077b11b 100644
--- a/chrome/test/data/extensions/api_test/webnavigation/test_history.js
+++ b/chrome/test/data/extensions/api_test/webnavigation/test_history.js
@@ -54,6 +54,56 @@ onload = function() {
           [ navigationOrder("a-") ]);
         chrome.tabs.update(tabId, { url: getURL('history/a.html') });
       },
+
+      // Manipulating history before parsing completed.
+      function historyBeforeParsing() {
+        expect([
+          { label: "a-onBeforeNavigate",
+            event: "onBeforeNavigate",
+            details: { frameId: 0,
+                       parentFrameId: -1,
+                       processId: 0,
+                       tabId: 0,
+                       timeStamp: 0,
+                       url: getURL('history/c.html') }},
+          { label: "a-onCommitted",
+            event: "onCommitted",
+            details: { frameId: 0,
+                       processId: 0,
+                       tabId: 0,
+                       timeStamp: 0,
+                       transitionQualifiers: [],
+                       transitionType: "link",
+                       url: getURL('history/c.html') }},
+          { label: "a-onHistoryStateUpdated",
+            event: "onHistoryStateUpdated",
+            details: { frameId: 0,
+                       processId: 0,
+                       tabId: 0,
+                       timeStamp: 0,
+                       transitionQualifiers: [],
+                       transitionType: "link",
+                       url: getURL('history/d.html') }},
+          { label: "a-onDOMContentLoaded",
+            event: "onDOMContentLoaded",
+            details: { frameId: 0,
+                       processId: 0,
+                       tabId: 0,
+                       timeStamp: 0,
+                       url: getURL('history/d.html') }},
+          { label: "a-onCompleted",
+            event: "onCompleted",
+            details: { frameId: 0,
+                       processId: 0,
+                       tabId: 0,
+                       timeStamp: 0,
+                       url: getURL('history/d.html') }}],
+          [ navigationOrder("a-"),
+            [ 'a-onCommitted',
+              'a-onHistoryStateUpdated',
+              'a-onDOMContentLoaded']]);
+        chrome.tabs.update(tabId, { url: getURL('history/c.html') });
+      },
     ]);
   });
 };