copy from toolkit/mozapps/update/test/unit/test_0201_app_launch_apply_update.js
copy to toolkit/mozapps/update/test/unit/test_0203_app_launch_apply_update.js
--- a/toolkit/mozapps/update/test/unit/test_0201_app_launch_apply_update.js
+++ b/toolkit/mozapps/update/test/unit/test_0203_app_launch_apply_update.js
@@ -3,33 +3,41 @@
  */
 
 /**
  * Test applying an update by applying an update in the background and
  * launching an application
  */
 
 /**
+ * This test is identical to test_0201_app_launch_apply_update.js, except
+ * that it locks the application directory when the test is launched to
+ * make the updater fall back to apply the update regularly.
+ */
+
+/**
  * The MAR file used for this test should not contain a version 2 update
  * manifest file (e.g. updatev2.manifest).
  */
 
-const TEST_ID = "0201";
+const TEST_ID = "0203";
 
 // Backup the updater.ini and use a custom one to prevent the updater from
 // launching a post update executable.
 const FILE_UPDATER_INI_BAK = "updater.ini.bak";
 
 // Number of milliseconds for each do_timeout call.
 const CHECK_TIMEOUT_MILLI = 1000;
 
 // Maximum number of milliseconds the process that is launched can run before
 // the test will try to kill it.
 const APP_TIMER_TIMEOUT = 15000;
 
+Components.utils.import("resource://gre/modules/ctypes.jsm");
+
 let gAppTimer;
 let gProcess;
 let gActiveUpdate;
 
 // Override getUpdatesRootDir on Mac because we need to apply the update
 // inside the bundle directory.
 function symlinkUpdateFilesIntoBundleDirectory() {
   if (!shouldAdjustPathsOnMac()) {
@@ -166,16 +174,37 @@ function run_test() {
   checkUpdateApplied();
 }
 
 function switchApp() {
   let launchBin = getLaunchBin();
   let args = getProcessArgs();
   logTestInfo("launching " + launchBin.path + " " + args.join(" "));
 
+  // Lock the installation directory
+  const LPCWSTR = ctypes.jschar.ptr;
+  const DWORD = ctypes.uint32_t;
+  const LPVOID = ctypes.voidptr_t;
+  const GENERIC_READ = 0x80000000;
+  const FILE_SHARE_READ = 1;
+  const FILE_SHARE_WRITE = 2;
+  const OPEN_EXISTING = 3;
+  const FILE_FLAG_BACKUP_SEMANTICS = 0x02000000;
+  const INVALID_HANDLE_VALUE = LPVOID(0xffffffff);
+  let kernel32 = ctypes.open("kernel32");
+  let CreateFile = kernel32.declare("CreateFileW", ctypes.default_abi,
+                                    LPVOID, LPCWSTR, DWORD, DWORD,
+                                    LPVOID, DWORD, DWORD, LPVOID);
+  logTestInfo(gWindowsBinDir.path);
+  let handle = CreateFile(gWindowsBinDir.path, GENERIC_READ,
+                          FILE_SHARE_READ | FILE_SHARE_WRITE, LPVOID(0),
+                          OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, LPVOID(0));
+  do_check_neq(handle.toString(), INVALID_HANDLE_VALUE.toString());
+  kernel32.close();
+
   gProcess = AUS_Cc["@mozilla.org/process/util;1"].
                 createInstance(AUS_Ci.nsIProcess);
   gProcess.init(launchBin);
 
   gAppTimer = AUS_Cc["@mozilla.org/timer;1"].createInstance(AUS_Ci.nsITimer);
   gAppTimer.initWithCallback(gTimerCallback, APP_TIMER_TIMEOUT,
                              AUS_Ci.nsITimer.TYPE_ONE_SHOT);
 

--- a/toolkit/mozapps/update/test/unit/xpcshell_updater_windows.ini
+++ b/toolkit/mozapps/update/test/unit/xpcshell_updater_windows.ini
@@ -22,8 +22,9 @@
 [test_0186_rmrfdirFileInUse_xp_win_complete.js]
 [test_0187_rmrfdirFileInUse_xp_win_partial.js]
 [test_0188_fileInUse_xp_win_complete.js]
 [test_0189_fileInUse_xp_win_partial.js]
 [test_0190_rmrfdirFileInUse_xp_win_complete.js]
 [test_0191_rmrfdirFileInUse_xp_win_partial.js]
 [test_0202_app_launch_apply_update_dirlocked.js]
 skip-if = true
+[test_0203_app_launch_apply_update.js]

copy from toolkit/mozapps/update/test_svc/unit/test_0201_app_launch_apply_update_svc.js
copy to toolkit/mozapps/update/test_svc/unit/test_0203_app_launch_apply_update_svc.js
--- a/toolkit/mozapps/update/test_svc/unit/test_0201_app_launch_apply_update_svc.js
+++ b/toolkit/mozapps/update/test_svc/unit/test_0203_app_launch_apply_update_svc.js
@@ -3,33 +3,41 @@
  */
 
 /**
  * Test applying an update by applying an update in the background and
  * launching an application
  */
 
 /**
+ * This test is identical to test_0201_app_launch_apply_update_svc.js, except
+ * that it locks the application directory when the test is launched to
+ * make the updater fall back to apply the update regularly.
+ */
+
+/**
  * The MAR file used for this test should not contain a version 2 update
  * manifest file (e.g. updatev2.manifest).
  */
 
-const TEST_ID = "0201_svc";
+const TEST_ID = "0203_svc";
 
 // Backup the updater.ini and use a custom one to prevent the updater from
 // launching a post update executable.
 const FILE_UPDATER_INI_BAK = "updater.ini.bak";
 
 // Number of milliseconds for each do_timeout call.
 const CHECK_TIMEOUT_MILLI = 1000;
 
 // Maximum number of milliseconds the process that is launched can run before
 // the test will try to kill it.
 const APP_TIMER_TIMEOUT = 15000;
 
+Components.utils.import("resource://gre/modules/ctypes.jsm");
+
 let gAppTimer;
 let gProcess;
 let gActiveUpdate;
 
 // Override getUpdatesRootDir on Mac because we need to apply the update
 // inside the bundle directory.
 function symlinkUpdateFilesIntoBundleDirectory() {
   if (!shouldAdjustPathsOnMac()) {
@@ -174,16 +182,37 @@ function run_test() {
   checkUpdateApplied();
 }
 
 function switchApp() {
   let launchBin = getLaunchBin();
   let args = getProcessArgs();
   logTestInfo("launching " + launchBin.path + " " + args.join(" "));
 
+  // Lock the installation directory
+  const LPCWSTR = ctypes.jschar.ptr;
+  const DWORD = ctypes.uint32_t;
+  const LPVOID = ctypes.voidptr_t;
+  const GENERIC_READ = 0x80000000;
+  const FILE_SHARE_READ = 1;
+  const FILE_SHARE_WRITE = 2;
+  const OPEN_EXISTING = 3;
+  const FILE_FLAG_BACKUP_SEMANTICS = 0x02000000;
+  const INVALID_HANDLE_VALUE = LPVOID(0xffffffff);
+  let kernel32 = ctypes.open("kernel32");
+  let CreateFile = kernel32.declare("CreateFileW", ctypes.default_abi,
+                                    LPVOID, LPCWSTR, DWORD, DWORD,
+                                    LPVOID, DWORD, DWORD, LPVOID);
+  logTestInfo(gWindowsBinDir.path);
+  let handle = CreateFile(gWindowsBinDir.path, GENERIC_READ,
+                          FILE_SHARE_READ | FILE_SHARE_WRITE, LPVOID(0),
+                          OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, LPVOID(0));
+  do_check_neq(handle.toString(), INVALID_HANDLE_VALUE.toString());
+  kernel32.close();
+
   gProcess = AUS_Cc["@mozilla.org/process/util;1"].
                 createInstance(AUS_Ci.nsIProcess);
   gProcess.init(launchBin);
 
   gAppTimer = AUS_Cc["@mozilla.org/timer;1"].createInstance(AUS_Ci.nsITimer);
   gAppTimer.initWithCallback(gTimerCallback, APP_TIMER_TIMEOUT,
                              AUS_Ci.nsITimer.TYPE_ONE_SHOT);
 

--- a/toolkit/mozapps/update/test_svc/unit/xpcshell.ini
+++ b/toolkit/mozapps/update/test_svc/unit/xpcshell.ini
@@ -36,8 +36,9 @@ tail =
 [test_0187_rmrfdirFileInUse_xp_win_partial_svc.js]
 [test_0188_fileInUse_xp_win_complete_svc.js]
 [test_0189_fileInUse_xp_win_partial_svc.js]
 [test_0190_rmrfdirFileInUse_xp_win_complete_svc.js]
 [test_0191_rmrfdirFileInUse_xp_win_partial_svc.js]
 [test_0200_app_launch_apply_update_svc.js]
 [test_0201_app_launch_apply_update_svc.js]
 [test_0202_app_launch_apply_update_dirlocked_svc.js]
+[test_0203_app_launch_apply_update_svc.js]

--- a/toolkit/mozapps/update/updater/updater.cpp
+++ b/toolkit/mozapps/update/updater/updater.cpp
@@ -2062,16 +2062,17 @@ UpdateThreadFunc(void *param)
                    NS_T("%s/Updated.app"),
 #else
                    NS_T("%s/updated"),
 #endif
                    installDir);
 
       ensure_remove_recursive(stageDir);
       WriteStatusText(sUsingService ? "pending-service" : "pending");
+      putenv("MOZ_PROCESS_UPDATES="); // We need to use -process-updates again in the tests
       reportRealResults = false; // pretend success
     }
   }
 
   if (reportRealResults) {
     if (rv) {
       LOG(("failed: %d\n", rv));
     }