Add tabs.onReplaced event to notify listeners of tabs being swapped due to prerendering or instant.

chrome/browser/prerender/prerender_browsertest.cc

Index: chrome/browser/prerender/prerender_browsertest.cc
diff --git a/chrome/browser/prerender/prerender_browsertest.cc b/chrome/browser/prerender/prerender_browsertest.cc
index 601fa246882357c2f0e268847334926bd7f58ae5..b6d5c07e18ec239a3683d75d20fdf1eb5ed815f9 100644
--- a/chrome/browser/prerender/prerender_browsertest.cc
+++ b/chrome/browser/prerender/prerender_browsertest.cc
@@ -2597,7 +2597,7 @@ IN_PROC_BROWSER_TEST_F(PrerenderBrowserTest, PrerenderSSLReferrerPolicy) {
   NavigateToDestURL();
 }
 
-// Test interaction of the webNavigation API with prerender.
+// Test interaction of the webNavigation and tabs API with prerender.
 class PrerenderBrowserTestWithExtensions : public PrerenderBrowserTest,
                                            public ExtensionApiTest {
  public:
@@ -2652,4 +2652,29 @@ IN_PROC_BROWSER_TEST_F(PrerenderBrowserTestWithExtensions, WebNavigation) {
   ASSERT_TRUE(catcher.GetNextResult()) << catcher.message();
 }
 
+IN_PROC_BROWSER_TEST_F(PrerenderBrowserTestWithExtensions, TabsApi) {
+  // PrerenderBrowserTest automatically started a test server. Restart it, so
+  // ExtensionApiTest can register its test parameters.
+  test_server()->Stop();

[Matt Perry, 2013/01/04 00:21:07]

This is a little janky. Can you make it an option to auto-start the test server,
and turn it off for this test? Starting the test server is moderately expensive.

[justinlin, 2013/01/04 12:43:50]

Done.

+  ASSERT_TRUE(StartTestServer());
+  extensions::FrameNavigationState::set_allow_extension_scheme(true);
+
+  // Wait for the extension to set itself up and return control to us.
+  ASSERT_TRUE(RunExtensionSubtest("tabs/on_replaced", "on_replaced.html"))
+      << message_;
+
+  ResultCatcher catcher;
+
+  PrerenderTestURL("files/prerender/prerender_page.html", FINAL_STATUS_USED, 1);
+
+  ChannelDestructionWatcher channel_close_watcher;
+  channel_close_watcher.WatchChannel(
+      chrome::GetActiveWebContents(browser())->GetRenderProcessHost());
+  NavigateToDestURL();
+  channel_close_watcher.WaitForChannelClose();
+
+  ASSERT_TRUE(IsEmptyPrerenderLinkManager());
+  ASSERT_TRUE(catcher.GetNextResult()) << catcher.message();
+}
+
 }  // namespace prerender