Keep browser process alive while there are platform apps with background pages running.

chrome/browser/sync/test/integration/apps_helper.cc

Index: chrome/browser/sync/test/integration/apps_helper.cc
diff --git a/chrome/browser/sync/test/integration/apps_helper.cc b/chrome/browser/sync/test/integration/apps_helper.cc
index fe9a37977afb1f9f34099924ee0d1042122c5311..77c83c9f6b419cc7911d47e288609899d6f43393 100644
--- a/chrome/browser/sync/test/integration/apps_helper.cc
+++ b/chrome/browser/sync/test/integration/apps_helper.cc
@@ -6,11 +6,14 @@
 
 #include "base/logging.h"
 #include "base/string_number_conversions.h"
+#include "chrome/browser/extensions/extension_process_manager.h"
+#include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/sync/test/integration/sync_app_helper.h"
 #include "chrome/browser/sync/test/integration/sync_datatype_helper.h"
 #include "chrome/browser/sync/test/integration/sync_extension_helper.h"
 #include "chrome/common/extensions/extension.h"
+#include "content/public/test/test_utils.h"
 
 using sync_datatype_helper::test;
 
@@ -20,6 +23,19 @@ std::string CreateFakeAppName(int index) {
   return "fakeapp" + base::IntToString(index);
 }
 
+void WaitForPlatformAppsToUnloadForProfile(Profile* profile) {
+  // Note this will hang if there are extensions with persistent background
+  // pages loaded.
+  ExtensionProcessManager* pm =
+      extensions::ExtensionSystem::Get(profile)->process_manager();
+  while (!pm->background_hosts().empty()) {
+    content::WindowedNotificationObserver destroyed_observer(
+        chrome::NOTIFICATION_EXTENSION_HOST_DESTROYED,
+        content::NotificationService::AllSources());
+    destroyed_observer.Wait();
+  }
+}
+
 }  // namespace
 
 namespace apps_helper {
@@ -126,4 +142,13 @@ void FixNTPOrdinalCollisions(Profile* profile) {
   SyncAppHelper::GetInstance()->FixNTPOrdinalCollisions(profile);
 }
 
+void WaitForPlatformAppsToUnload() {
+  // First run any pending tasks to allow any about to load background
+  // pages to load.
+  MessageLoop::current()->RunUntilIdle();
+  for (int i = 0; i < test()->num_clients(); ++i)
+    WaitForPlatformAppsToUnloadForProfile(test()->GetProfile(i));
+  WaitForPlatformAppsToUnloadForProfile(test()->verifier());
+}
+
 }  // namespace apps_helper