Now closes existing background contents if app opens a new one.

chrome/test/data/extensions/api_test/app_background_page/two_pages/test.html

Index: chrome/test/data/extensions/api_test/app_background_page/two_pages/test.html
diff --git a/chrome/test/data/extensions/api_test/app_background_page/two_pages/test.html b/chrome/test/data/extensions/api_test/app_background_page/two_pages/test.html
new file mode 100644
index 0000000000000000000000000000000000000000..b88829a6ef29e10913a918b51b38ae8efff27a8b
--- /dev/null
+++ b/chrome/test/data/extensions/api_test/app_background_page/two_pages/test.html
@@ -0,0 +1,95 @@
+<script>
+// This test runs through an expected use of a live background page:
+// - A live (web-extent) web page is loaded (a.html), which opens the background
+//   page.
+// - The first page is closed and a second live web page is loaded (c.html),
+//   which uses a different name. This second page also checks a counter which
+//   should have a value consistent with being called once.
+// - We then reopen the first page. This first page also checks a counter
+//   which should have a value consistent with the page being newly opened.
+// - The background page closes itself.
+
+var pageA;
+var pageC;
+var step = 0;
+
+var pagePrefix =
+    'http://a.com:PORT/files/extensions/api_test/app_background_page/common';
+
+// Dispatch "tunneled" functions from the live web pages to this testing page.
+chrome.extension.onRequest.addListener(function(request) {
+  window[request.name](request.args);
+});
+
+// At no point should a window be created that contains the background page
+// (bg.html).
+chrome.tabs.onUpdated.addListener(function(tabId, changeInfo, tab) {
+  if (tab.url.match("bg\.html$")) {
+    chrome.test.notifyFail("popup opened instead of background page");
+  }
+});
+
+// Start the test by opening the first page in the app.
+window.onload = function() {
+  // We wait for window.onload before getting the test config.  If the
+  // config is requested before onload, then sometimes onload has already
+  // fired by the time chrome.test.getConfig()'s callback runs.
+  chrome.test.getConfig(function(config) {
+    var a_url =
+        pagePrefix.replace(/PORT/, config.testServer.port) + '/a.html';
+    chrome.tabs.create({ 'url': a_url }, function(tab) {
+      pageA = tab;
+    });
+  });
+}
+
+// Background page opened.
+function onBackgroundPageLoaded() {
+  // There are 3 steps to this test:
+  // #1: page A just opened and opened its background page, so we close pageA
+  //     and open pageC.
+  // #2: page C just opened and opened its background page, so we close pageC
+  //     and reopen pageA.
+  // #3: page A opened again and opened its background page, so we're done.
+  if (step == 0) {
+    // Close A, open C.
+    chrome.tabs.remove(pageA.id, function() {
+      chrome.test.getConfig(function(config) {
+        var c_url =
+            pagePrefix.replace(/PORT/, config.testServer.port) + '/c.html';
+        chrome.tabs.create({ url: c_url }, function(tab) {
+          pageC = tab;
+        });
+      });
+    });
+  } else if (step == 1) {
+    // Close C, re-open A
+    chrome.tabs.remove(pageC.id, function() {
+      chrome.test.getConfig(function(config) {
+        var a_url =
+            pagePrefix.replace(/PORT/, config.testServer.port) + '/a.html';
+        chrome.tabs.create({ url: a_url }, function(tab) {
+          pageA = tab;
+        });
+      });
+    });
+  } else if (step == 2) {
+    chrome.test.notifyPass();
+  } else {
+    chrome.test.notifyFail("onBackgroundPageLoaded() called too many times");
+  }
+  step++;
+}
+
+// Background page responded to pageC.
+function onBackgroundPageResponded() {
+  chrome.test.notifyFail("onBackgroundPageResponded called unexpectedly");
+}
+
+// The background counter check found an unexpected value (most likely caused
+// by an unwanted navigation.
+function onCounterError() {
+  chrome.test.notifyFail("checkCounter found an unexpected value");
+}
+
+</script>