Add onChanged callback for chrome.sessions API.

chrome/test/data/extensions/api_test/sessions/sessions.js

Index: chrome/test/data/extensions/api_test/sessions/sessions.js
diff --git a/chrome/test/data/extensions/api_test/sessions/sessions.js b/chrome/test/data/extensions/api_test/sessions/sessions.js
index 431edbec72fb11ed0a052bebb3a721a68cc1e13f..f7e475ec7d419546076a06552115fa404d28d135 100644
--- a/chrome/test/data/extensions/api_test/sessions/sessions.js
+++ b/chrome/test/data/extensions/api_test/sessions/sessions.js
@@ -59,6 +59,33 @@ function checkEntries(expectedEntries, actualEntries) {
   });
 }
 
+function checkOnChangedEvent(expectedCallbackCount) {
+  var callbackCount = 0;
+  var done = chrome.test.listenForever(chrome.sessions.onChanged, function() {
+      callbackCount++;
+    }
+  );
+
+  return function() {
+    var maxRetry = 10, retry = 1;
+    var checkEvent = function() {
+      if (callbackCount < expectedCallbackCount) {
+        console.log("Waiting for " +
+                    (expectedCallbackCount - callbackCount) +
+                    " more onChanged events");
+        retry++;
+        if (retry < maxRetry) {
+          window.setTimeout(checkEvent, 100);
+          return;
+        }
+      }
+      assertEq(callbackCount, expectedCallbackCount);
+      done();
+    };
+    window.setTimeout(checkEvent, 100);

[not at google - send to devlin, 2014/03/28 15:51:10]

100*10ms is too small, this only gives the test 1 second to finish which is
going to be flaky. I'd say give it 10 seconds, or really, just don't have a max
number of retries at all and just let the normal test timeout (30s) kick in.

So yeah. No maxRetry. and increase to 1s so that while it's waiting it doesn't
totally spam the console output.

+  };
+}
+
 chrome.test.runTests([
   // After setupWindows
   //
@@ -108,6 +135,8 @@ chrome.test.runTests([
   function retrieveClosedTabs() {
     // Check that the recently closed list contains what we expect
     // after removing tabs.
+    var checkEvent = checkOnChangedEvent(2);
+
     callForEach(
       chrome.tabs.remove,
       firstWindowTabIds.slice(0, 2).reverse(),
@@ -125,6 +154,7 @@ chrome.test.runTests([
             entries.forEach(function(entry) {
               recentlyClosedTabIds.push(entry.tab.sessionId);
             });
+            checkEvent();
           })
         );
       }
@@ -134,6 +164,8 @@ chrome.test.runTests([
   function retrieveClosedWindows() {
     // Check that the recently closed list contains what we expect
     // after removing windows.
+    var checkEvent = checkOnChangedEvent(2);
+
     callForEach(
       chrome.windows.remove,
       windowIds.slice(1, 3).reverse(),
@@ -154,6 +186,7 @@ chrome.test.runTests([
             entries.forEach(function(entry) {
               recentlyClosedWindowIds.push(entry.window.sessionId);
             });
+            checkEvent();
           })
         );
       }
@@ -197,6 +230,8 @@ chrome.test.runTests([
   },
 
   function restoreClosedTabs() {
+    var checkEvent = checkOnChangedEvent(2);
+
     chrome.windows.get(windowIds[0], {"populate": true},
       callbackPass(function(win) {
         var tabCountBeforeRestore = win.tabs.length;
@@ -212,6 +247,7 @@ chrome.test.runTests([
             win.tabs.forEach(function(tab, i) {
               assertEq(pages[i++], tab.url);
             });
+            checkEvent();
           })
         );
       })
@@ -219,6 +255,8 @@ chrome.test.runTests([
   },
 
   function restoreTabInClosedWindow() {
+    var checkEvent = checkOnChangedEvent(1);
+
     chrome.windows.getAll({"populate": true}, callbackPass(function(win) {
       var windowCountBeforeRestore = win.length;
       chrome.sessions.restore(recentlyClosedSecondWindowTabIds[0],
@@ -229,6 +267,7 @@ chrome.test.runTests([
               assertEq(windowCountBeforeRestore + 1, win.length);
               assertEq(1, win[win.length - 1].tabs.length);
               assertEq(pages[0], win[win.length - 1].tabs[0].url);
+              checkEvent();
             })
           );
         })
@@ -237,11 +276,14 @@ chrome.test.runTests([
   },
 
   function restoreClosedWindows() {
+    var checkEvent = checkOnChangedEvent(1);
+
     chrome.windows.getAll({"populate": true}, callbackPass(function(win) {
       var windowCountBeforeRestore = win.length;
       chrome.sessions.restore(recentlyClosedWindowIds[0],
           function(win_session) {
             assertEq(1, win_session.window.tabs.length);
+            checkEvent();
           });
       function done() {
         chrome.windows.getAll({"populate": true},
@@ -285,6 +327,8 @@ chrome.test.runTests([
   },
 
   function restoreMostRecentEntry() {
+    var checkEvent = checkOnChangedEvent(1);
+
     chrome.windows.getAll({"populate": true}, callbackPass(function(win) {
       var windowCountBeforeRestore = win.length;
       chrome.sessions.restore(callbackPass(function(win_session) {
@@ -292,6 +336,7 @@ chrome.test.runTests([
         chrome.windows.getAll({"populate": true},
           callbackPass(function(win) {
             assertEq(windowCountBeforeRestore + 1, win.length);
+            checkEvent();
           })
         );
       }));