Speculative resource prefetching - Test fixes.

- Removing dcheck that two navigations on the same renderview with the same url should not have the same creation time. It looks like it is possible for tests to be able to do this and theoretically it is possible for this to happen in production. The code already this handles this case well, so the check will not be missed.

- Add a check to see if WebContents returns empty URL before calling OnNavigationComplete.


Review URL: https://chromiumcodereview.appspot.com/10825118

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@149353 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/predictors/resource_prefetch_predictor.cc

@@ -326,14 +326,6 @@ void ResourcePrefetchPredictor::OnMainFrameRequest(
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK_EQ(INITIALIZED, initialization_state_);
 
-  // TODO(shishir): Remove this code after verifying that the same navigation is
-  // not seen multiple times.
-  NavigationMap::const_iterator it =
-      inflight_navigations_.find(request.navigation_id);
-  if (it != inflight_navigations_.end()) {
-    DCHECK(it->first.creation_time != request.navigation_id.creation_time);
-  }
-
   // Cleanup older navigations.
   CleanupAbandonedNavigations(request.navigation_id);
 
@@ -416,7 +408,10 @@ void ResourcePrefetchPredictor::Observe(
       const content::WebContents* web_contents =
           content::Source<content::WebContents>(source).ptr();
       NavigationID navigation_id(*web_contents);
-      OnNavigationComplete(navigation_id);
+      // WebContents can return an empty URL if the navigation entry
+      // corresponding to the navigation has not been created yet.
+      if (!navigation_id.main_frame_url.is_empty())
+        OnNavigationComplete(navigation_id);
       break;
     }