Speed up NetInternalsTest.netInternalsPrerenderViewFail by

creating one less process.  Same method cannot be used for
NetInternalsTest.netInternalsPrerenderViewSucceed, unfortunately.

R=eroman@chromium.org
BUG=119731

Review URL: http://codereview.chromium.org/9836046

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@128658 0039d316-1c4b-4281-b951-d872f2087c98

chrome/test/data/webui/net_internals/prerender_view.js

@@ -114,10 +114,21 @@ PrerenderTask.prototype = {
   startPrerendering_: function(prerenderInfo) {
     expectEquals(0, prerenderInfo.active.length);
     expectEquals(0, prerenderInfo.history.length);
-    chrome.send('prerenderPage', [this.url_]);
     if (this.shouldSucceed_) {
+      chrome.send('prerenderPage', [this.url_]);
+
       this.state_ = STATE.NEED_NAVIGATE;
     } else {
+      // If the prerender is going to fail, we can add the prerender link to the
+      // current document, so we will create one less process.  Unfortunately,
+      // if the prerender is going to succeed, we have to create a new process
+      // with the prerender link, to avoid the prerender being cancelled due to
+      // a session storage namespace mismatch.
+      var link = document.createElement('link');
+      link.rel = 'prerender';
+      link.href = this.url_;
+      document.head.appendChild(link);
+
       this.state_ = STATE.HISTORY_WAIT;
     }
   },