Switch on-demand update checks to the less-old GoogleUpdate3 API.

chrome/browser/google/google_update_win.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/google/google_update_win.h"
 
 #include <atlbase.h>
 #include <atlcom.h>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/files/file_path.h"
 #include "base/location.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/sparse_histogram.h"
 #include "base/path_service.h"
+#include "base/sequenced_task_runner_helpers.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
-#include "base/task_runner.h"
+#include "base/strings/utf_string_conversions.h"
 #include "base/thread_task_runner_handle.h"
+#include "base/time/time.h"
+#include "base/win/scoped_bstr.h"
 #include "base/win/windows_version.h"
 #include "chrome/grit/generated_resources.h"
 #include "chrome/installer/util/browser_distribution.h"
-#include "chrome/installer/util/google_update_settings.h"
 #include "chrome/installer/util/helper.h"
 #include "chrome/installer/util/install_util.h"
-#include "content/public/browser/browser_thread.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/win/atl_module.h"
+#include "ui/gfx/geometry/safe_integer_conversions.h"
 
 namespace {
 
-OnDemandAppsClassFactory* g_google_update_factory = nullptr;
+// The status of the upgrade. These values are used for a histogram. Do not
+// reorder.
+enum GoogleUpdateUpgradeStatus {
+  // The upgrade has started. DEPRECATED.
+  // UPGRADE_STARTED = 0,
+  // A check for upgrade has been initiated. DEPRECATED.
+  // UPGRADE_CHECK_STARTED = 1,
+  // An update is available.
+  UPGRADE_IS_AVAILABLE = 2,
+  // The upgrade happened successfully.
+  UPGRADE_SUCCESSFUL = 3,
+  // No need to upgrade, Chrome is up to date.
+  UPGRADE_ALREADY_UP_TO_DATE = 4,
+  // An error occurred.
+  UPGRADE_ERROR = 5,
+  NUM_UPGRADE_STATUS
+};
+
+GoogleUpdate3ClassFactory* g_google_update_factory = nullptr;
+
+// The time interval, in milliseconds, between polls to Google Update. This
+// value was chosen unscientificaly during an informal discussion.
+const int64_t kGoogleUpdatePollIntervalMs = 250;
+
+// Constants from Google Update.
+const HRESULT GOOPDATE_E_APP_UPDATE_DISABLED_BY_POLICY = 0x80040813;
+const HRESULT GOOPDATEINSTALL_E_INSTALLER_FAILED = 0x80040902;
 
 // Check if the currently running instance can be updated by Google Update.
 // Returns GOOGLE_UPDATE_NO_ERROR only if the instance running is a Google
 // Chrome distribution installed in a standard location.
 GoogleUpdateErrorCode CanUpdateCurrentChrome(
     const base::FilePath& chrome_exe_path,
-    bool system_level) {
+    bool system_level_install) {
 #if !defined(GOOGLE_CHROME_BUILD)
   return CANNOT_UPGRADE_CHROME_IN_THIS_DIRECTORY;
 #else
-  DCHECK_NE(InstallUtil::IsPerUserInstall(chrome_exe_path), system_level);
+  DCHECK_NE(InstallUtil::IsPerUserInstall(chrome_exe_path),
+            system_level_install);
   BrowserDistribution* dist = BrowserDistribution::GetDistribution();
   base::FilePath user_exe_path = installer::GetChromeInstallPath(false, dist);
   base::FilePath machine_exe_path = installer::GetChromeInstallPath(true, dist);
   if (!base::FilePath::CompareEqualIgnoreCase(chrome_exe_path.value(),
                                         user_exe_path.value()) &&
       !base::FilePath::CompareEqualIgnoreCase(chrome_exe_path.value(),
                                         machine_exe_path.value())) {
     return CANNOT_UPGRADE_CHROME_IN_THIS_DIRECTORY;
   }
 
-  base::string16 app_guid = installer::GetAppGuidForUpdates(system_level);
-  DCHECK(!app_guid.empty());
-
-  GoogleUpdateSettings::UpdatePolicy update_policy =
-      GoogleUpdateSettings::GetAppUpdatePolicy(app_guid, NULL);
-
-  if (update_policy == GoogleUpdateSettings::UPDATES_DISABLED)
-    return GOOGLE_UPDATE_DISABLED_BY_POLICY;
-
-  if (update_policy == GoogleUpdateSettings::AUTO_UPDATES_ONLY)
-    return GOOGLE_UPDATE_DISABLED_BY_POLICY_AUTO_ONLY;
-
   return GOOGLE_UPDATE_NO_ERROR;
 #endif
 }
 
 // Creates an instance of a COM Local Server class using either plain vanilla
 // CoCreateInstance, or using the Elevation moniker if running on Vista.
 // hwnd must refer to a foregound window in order to get the UAC prompt
 // showing up in the foreground if running on Vista. It can also be NULL if
 // background UAC prompts are desired.
 HRESULT CoCreateInstanceAsAdmin(REFCLSID class_id,
@@ skipping 23 matching lines @@
     bind_opts.hwnd = hwnd;
 
     return CoGetObject(elevation_moniker_name.c_str(), &bind_opts, interface_id,
                        interface_ptr);
   }
 
   return CoCreateInstance(class_id, NULL, CLSCTX_LOCAL_SERVER, interface_id,
                           interface_ptr);
 }
 
-HRESULT CreateOnDemandAppsClass(
-    bool system_level,
-    bool install_if_newer,
+HRESULT CreateGoogleUpdate3WebClass(
+    bool system_level_install,
+    bool install_update_if_possible,
     gfx::AcceleratedWidget elevation_window,
-    base::win::ScopedComPtr<IGoogleUpdate>* on_demand) {
+    base::win::ScopedComPtr<IGoogleUpdate3Web>* google_update) {
   if (g_google_update_factory)
-    return g_google_update_factory->Run(on_demand);
+    return g_google_update_factory->Run(google_update);
 
   // For a user-level install, update checks and updates can both be done by a
-  // normal user with the UserAppsClass.
-  if (!system_level)
-    return on_demand->CreateInstance(CLSID_OnDemandUserAppsClass);
+  // normal user with the UserClass.
+  if (!system_level_install)
+    return google_update->CreateInstance(CLSID_GoogleUpdate3WebUserClass);
 
   // For a system-level install, update checks can be done by a normal user with
-  // the MachineAppsClass.
-  if (!install_if_newer)
-    return on_demand->CreateInstance(CLSID_OnDemandMachineAppsClass);
+  // the ServiceClass.

[S. Ganesh, 2015/05/13 20:21:40]

MachineClass

[grt (UTC plus 2), 2015/05/13 20:36:38]

Nice catch. Will take care of in a follow-on CL.

+  if (!install_update_if_possible)
+    return google_update->CreateInstance(CLSID_GoogleUpdate3WebMachineClass);
 
   // For a system-level install, an update requires Admin privileges for writing
-  // to %ProgramFiles%. Elevate while instantiating the MachineAppsClass.
-  return CoCreateInstanceAsAdmin(CLSID_OnDemandMachineAppsClass,
-                                 IID_IGoogleUpdate, elevation_window,
-                                 on_demand->ReceiveVoid());
-}
-
-
-// GoogleUpdateJobObserver -----------------------------------------------------
-
-// The GoogleUpdateJobObserver COM class is responsible for receiving status
-// reports from google Update. It keeps track of the progress as Google Update
-// notifies this observer and runs a completion callback once Google Update
-// reports that it is done.
-class GoogleUpdateJobObserver : public CComObjectRootEx<CComSingleThreadModel>,
-                                public IJobObserver {
- public:
-  BEGIN_COM_MAP(GoogleUpdateJobObserver)
-    COM_INTERFACE_ENTRY(IJobObserver)
-  END_COM_MAP()
-
-  GoogleUpdateJobObserver();
-  virtual ~GoogleUpdateJobObserver();
-
-  // Sets the callback to be invoked when Google Update reports that the job is
-  // done.
-  void set_on_complete_callback(const base::Closure& on_complete_callback) {
-    on_complete_callback_ = on_complete_callback;
-  }
-
-  // Returns the results of the update operation.
-  GoogleUpdateUpgradeResult result() const {
-    // Intermediary steps should never be reported to the client.
-    DCHECK_NE(UPGRADE_STARTED, result_);
-    DCHECK_NE(UPGRADE_CHECK_STARTED, result_);
-    return result_;
-  }
-
-  // Returns which version Google Update found on the server (if a more
-  // recent version was found). Otherwise, this will be blank.
-  base::string16 new_version() const { return new_version_; }
-
-  // Returns the Google Update supplied error string that describes the error
-  // that occurred during the update check/upgrade.
-  base::string16 error_message() const { return error_message_; }
-
- private:
-  // IJobObserver:
-  STDMETHOD(OnShow)() override;
-  STDMETHOD(OnCheckingForUpdate)() override;
-  STDMETHOD(OnUpdateAvailable)(const TCHAR* version_string) override;
-  STDMETHOD(OnWaitingToDownload)() override;
-  STDMETHOD(OnDownloading)(int time_remaining_ms, int pos) override;
-  STDMETHOD(OnWaitingToInstall)() override;
-  STDMETHOD(OnInstalling)() override;
-  STDMETHOD(OnPause)() override;
-  STDMETHOD(OnComplete)(LegacyCompletionCodes code, const TCHAR* text) override;
-  STDMETHOD(SetEventSink)(IProgressWndEvents* event_sink) override;
-
-  // The task runner associated with the thread in which the job runs.
-  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
-
-  // A callback to be run to complete processing;
-  base::Closure on_complete_callback_;
-
-  // The status/result of the Google Update operation.
-  GoogleUpdateUpgradeResult result_;
-
-  // The version string Google Update found.
-  base::string16 new_version_;
-
-  // An error message, if any.
-  base::string16 error_message_;
-
-  // Allows us control the upgrade process to a small degree. After OnComplete
-  // has been called, this object can not be used.
-  base::win::ScopedComPtr<IProgressWndEvents> event_sink_;
-
-  DISALLOW_COPY_AND_ASSIGN(GoogleUpdateJobObserver);
-};
-
-GoogleUpdateJobObserver::GoogleUpdateJobObserver()
-    : task_runner_(base::ThreadTaskRunnerHandle::Get()),
-      result_(UPGRADE_ERROR) {
-}
-
-GoogleUpdateJobObserver::~GoogleUpdateJobObserver() {
-}
-
-STDMETHODIMP GoogleUpdateJobObserver::OnShow() {
-  return S_OK;
-}
-
-STDMETHODIMP GoogleUpdateJobObserver::OnCheckingForUpdate() {
-  result_ = UPGRADE_CHECK_STARTED;
-  return S_OK;
-}
-
-STDMETHODIMP GoogleUpdateJobObserver::OnUpdateAvailable(
-    const TCHAR* version_string) {
-  result_ = UPGRADE_IS_AVAILABLE;
-  new_version_ = version_string;
-  return S_OK;
-}
-
-STDMETHODIMP GoogleUpdateJobObserver::OnWaitingToDownload() {
-  return S_OK;
-}
-
-STDMETHODIMP GoogleUpdateJobObserver::OnDownloading(int time_remaining_ms,
-                                                    int pos) {
-  return S_OK;
-}
-
-STDMETHODIMP GoogleUpdateJobObserver::OnWaitingToInstall() {
-  return S_OK;
-}
-
-STDMETHODIMP GoogleUpdateJobObserver::OnInstalling() {
-  result_ = UPGRADE_STARTED;
-  return S_OK;
-}
-
-STDMETHODIMP GoogleUpdateJobObserver::OnPause() {
-  return S_OK;
-}
-
-STDMETHODIMP GoogleUpdateJobObserver::OnComplete(LegacyCompletionCodes code,
-                                                 const TCHAR* text) {
-  if (code == COMPLETION_CODE_ERROR) {
-    error_message_ = text;
-    result_ = UPGRADE_ERROR;
-  } else {
-    // Everything that isn't an error is some form of success. Chrome doesn't
-    // support any of the fancy codes (e.g., COMPLETION_CODE_REBOOT), but they
-    // shouldn't be generated anyway.
-    LOG_IF(DFATAL, (code != COMPLETION_CODE_SUCCESS &&
-                    code != COMPLETION_CODE_SUCCESS_CLOSE_UI))
-        << "Unexpected LegacyCompletionCode from IGoogleUpdate: " << code;
-    if (result_ == UPGRADE_STARTED)
-      result_ = UPGRADE_SUCCESSFUL;
-    else if (result_ == UPGRADE_CHECK_STARTED)
-      result_ = UPGRADE_ALREADY_UP_TO_DATE;
-  }
-
-  event_sink_ = NULL;
-
-  task_runner_->PostTask(FROM_HERE, on_complete_callback_);
-  return S_OK;
-}
-
-STDMETHODIMP GoogleUpdateJobObserver::SetEventSink(
-    IProgressWndEvents* event_sink) {
-  event_sink_ = event_sink;
-  return S_OK;
-}
-
+  // to %ProgramFiles%. Elevate while instantiating the ServiceClass.
+  return CoCreateInstanceAsAdmin(CLSID_GoogleUpdate3WebMachineClass,
+                                 IID_IGoogleUpdate3Web, elevation_window,
+                                 google_update->ReceiveVoid());
+}
 
 // UpdateCheckDriver -----------------------------------------------------------
 
 // A driver that is created and destroyed on the caller's thread and drives
 // Google Update on another.
 class UpdateCheckDriver {
  public:
-  // Runs an update check on |task_runner|, invoking |callback| on the caller's
-  // thread upon completion. |task_runner| must run a TYPE_UI message loop if
-  // the default IGoogleUpdate on-demand COM class is used.
-  static void RunUpdateCheck(const scoped_refptr<base::TaskRunner>& task_runner,
-                             bool install_if_newer,
-                             gfx::AcceleratedWidget elevation_window,
-                             const UpdateCheckCallback& callback);
+  // Runs an update check on |task_runner|, invoking methods of |delegate| on
+  // the caller's thread to report progress and final results.
+  static void RunUpdateCheck(
+      const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+      const std::string& locale,
+      bool install_update_if_possible,
+      gfx::AcceleratedWidget elevation_window,
+      const base::WeakPtr<UpdateCheckDelegate>& delegate);
 
  private:
   friend class base::DeleteHelper<UpdateCheckDriver>;
 
-  explicit UpdateCheckDriver(const UpdateCheckCallback& callback);
-
-  // Runs the caller's update check callback with the results of the operation.
+  UpdateCheckDriver(
+      const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+      const std::string& locale,
+      bool install_update_if_possible,
+      gfx::AcceleratedWidget elevation_window,
+      const base::WeakPtr<UpdateCheckDelegate>& delegate);
+
+  // Invokes a completion or error method on the caller's delegate, as
+  // appropriate.
   ~UpdateCheckDriver();
 
   // Starts an update check.
-  void BeginUpdateCheck(bool install_if_newer,
-                        gfx::AcceleratedWidget elevation_window);
-
-  // Helper function for starting an update check. Returns true if the check was
-  // properly started, in which case CompleteUpdateCheck will be invoked upon
-  // completion to return results to the caller on its own thread.
-  bool BeginUpdateCheckInternal(bool install_if_newer,
-                                gfx::AcceleratedWidget elevation_window);
-
-  // Invoked when results are in from Google Update.
-  void CompleteUpdateCheck();
-
-  // Prepares |results| to return the upgrade error indicated by |error_code|
-  // and |hr|. The string " -- system level" is included in the generated error
-  // message when |system_level| is true.
+  void BeginUpdateCheck();
+
+  // Returns the result of initiating an update check. Sets |error_code| if the
+  // result is any kind of failure.
+  HRESULT BeginUpdateCheckInternal(GoogleUpdateErrorCode* error_code);
+
+  // Sets status_ to UPGRADE_ERROR, error_code_ to |error_code|, hresult_ to
+  // |hresult|, installer_exit_code_ to |installer_exit_code|, and
+  // error_message_ to a composition of all values suitable for display to the
+  // user. This call should be followed by deletion of the driver, which will
+  // result in the caller being notified via its delegate.
   void OnUpgradeError(GoogleUpdateErrorCode error_code,
-                      HRESULT hr,
-                      bool system_level);
-
-  // The caller's task runner, on which |result_callback_| will be run.
+                      HRESULT hresult,
+                      int installer_exit_code,
+                      const base::string16& error_string);
+
+  // Returns true if |current_state| and |state_value| can be obtained from the
+  // ongoing update check. Otherwise, populates |hresult| with the reason they
+  // could not be obtained.
+  bool GetCurrentState(base::win::ScopedComPtr<ICurrentState>* current_state,
+                       CurrentState* state_value,
+                       HRESULT* hresult) const;
+
+  // Returns true if |current_state| and |state_value| constitute an error state
+  // for the ongoing update check, in which case |error_code| is populated with
+  // one of GOOGLE_UPDATE_ERROR_UPDATING, GOOGLE_UPDATE_DISABLED_BY_POLICY, or
+  // GOOGLE_UPDATE_ONDEMAND_CLASS_REPORTED_ERROR. |hresult| is populated with
+  // the most relevant HRESULT (which may be a value from Google Update; see
+  // https://code.google.com/p/omaha/source/browse/trunk/base/error.h). In case
+  // Chrome's installer failed during execution, |installer_exit_code| may be
+  // populated with its process exit code (see enum installer::InstallStatus in
+  // chrome/installer/util/util_constants.h); otherwise, it will be -1.
+  // |error_string| will be populated with a completion message if one is
+  // provided by Google Update.
+  bool IsErrorState(const base::win::ScopedComPtr<ICurrentState>& current_state,
+                    CurrentState state_value,
+                    GoogleUpdateErrorCode* error_code,
+                    HRESULT* hresult,
+                    int* installer_exit_code,
+                    base::string16* error_string) const;
+
+  // Returns true if |current_state| and |state_value| constitute a final state
+  // for the ongoing update check, in which case |upgrade_status| is populated
+  // with one of UPGRADE_ALREADY_UP_TO_DATE or UPGRADE_IS_AVAILABLE (in case a
+  // pure check is being performed rather than an update) or UPGRADE_SUCCESSFUL
+  // (in case an update is being performed). For the UPGRADE_IS_AVAILABLE case,
+  // |new_version| will be populated with the available version, if provided by
+  // Google Update.
+  bool IsFinalState(const base::win::ScopedComPtr<ICurrentState>& current_state,
+                    CurrentState state_value,
+                    GoogleUpdateUpgradeStatus* upgrade_status,
+                    base::string16* new_version) const;
+
+  // Returns true if |current_state| and |state_value| constitute an
+  // intermediate state for the ongoing update check. |new_version| will be
+  // populated with the version to be installed if it is provided by Google
+  // Update for the current state. |progress| will be populated with a number
+  // between 0 and 100 according to how far Google Update has progressed in the
+  // download and install process.
+  bool IsIntermediateState(
+      const base::win::ScopedComPtr<ICurrentState>& current_state,
+      CurrentState state_value,
+      base::string16* new_version,
+      int* progress) const;
+
+  // Polls Google Update to determine the state of the ongoing check or
+  // update. If the process has reached a terminal state, this instance will be
+  // deleted and the caller will be notified of the final status. Otherwise, the
+  // caller will be notified of the intermediate state (iff it differs from a
+  // previous notification) and another future poll will be scheduled.
+  void PollGoogleUpdate();
+
+  // The task runner on which the update checks runs.
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+
+  // The caller's task runner, on which methods of |delegate_| will be invoked.
   scoped_refptr<base::SingleThreadTaskRunner> result_runner_;
 
-  // The caller's callback to be run when the update check is compelte.
-  UpdateCheckCallback result_callback_;
-
-  // The results of the update check.
-  GoogleUpdateUpgradeResult result_;
+  // The UI locale.
+  std::string locale_;
+
+  // False to only check for an update; true to also install one if available.
+  bool install_update_if_possible_;
+
+  // A parent window in case any UX is required (e.g., an elevation prompt).
+  gfx::AcceleratedWidget elevation_window_;
+
+  // The caller's delegate by which feedback is conveyed.
+  base::WeakPtr<UpdateCheckDelegate> delegate_;
+
+  // True if operating on a per-machine installation rather than a per-user one.
+  bool system_level_install_;
+
+  // The on-demand updater that is doing the work.
+  base::win::ScopedComPtr<IGoogleUpdate3Web> google_update_;
+
+  // An app bundle containing the application being updated.
+  base::win::ScopedComPtr<IAppBundleWeb> app_bundle_;
+
+  // The application being updated (Chrome, Chrome Binaries, or Chrome SxS).
+  base::win::ScopedComPtr<IAppWeb> app_;
+
+  // The progress value reported most recently to the caller.
+  int last_reported_progress_;
+
+  // The results of the update check to be logged via UMA and/or reported to the
+  // caller.
+  GoogleUpdateUpgradeStatus status_;
   GoogleUpdateErrorCode error_code_;
   base::string16 error_message_;
-  base::string16 version_;
+  base::string16 new_version_;
   HRESULT hresult_;
-
-  // A direct pointer to the job observer by which the driver is notified of
-  // interesting events from Google Update.
-  CComObject<GoogleUpdateJobObserver>* job_observer_;
-
-  // A scoped pointer to |job_observer_| that holds a reference to it, keeping
-  // it alive.
-  base::win::ScopedComPtr<IJobObserver> job_holder_;
-
-  // The on-demand updater that is doing the work.
-  base::win::ScopedComPtr<IGoogleUpdate> on_demand_;
+  int installer_exit_code_;
 
   DISALLOW_COPY_AND_ASSIGN(UpdateCheckDriver);
 };
 
 // static
 void UpdateCheckDriver::RunUpdateCheck(
-    const scoped_refptr<base::TaskRunner>& task_runner,
-    bool install_if_newer,
+    const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+    const std::string& locale,
+    bool install_update_if_possible,
     gfx::AcceleratedWidget elevation_window,
-    const UpdateCheckCallback& callback) {
+    const base::WeakPtr<UpdateCheckDelegate>& delegate) {
   // The driver is owned by itself, and will self-destruct when its work is
   // done.
-  UpdateCheckDriver* driver = new UpdateCheckDriver(callback);
-  task_runner->PostTask(
-      FROM_HERE,
-      base::Bind(&UpdateCheckDriver::BeginUpdateCheck, base::Unretained(driver),
-                 install_if_newer, elevation_window));
+  UpdateCheckDriver* driver =
+      new UpdateCheckDriver(task_runner, locale, install_update_if_possible,
+                            elevation_window, delegate);
+  task_runner->PostTask(FROM_HERE,
+                        base::Bind(&UpdateCheckDriver::BeginUpdateCheck,
+                                   base::Unretained(driver)));
 }
 
 // Runs on the caller's thread.
-UpdateCheckDriver::UpdateCheckDriver(const UpdateCheckCallback& callback)
-    : result_runner_(base::ThreadTaskRunnerHandle::Get()),
-      result_callback_(callback),
-      result_(UPGRADE_ERROR),
+UpdateCheckDriver::UpdateCheckDriver(
+    const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+    const std::string& locale,
+    bool install_update_if_possible,
+    gfx::AcceleratedWidget elevation_window,
+    const base::WeakPtr<UpdateCheckDelegate>& delegate)
+    : task_runner_(task_runner),
+      result_runner_(base::ThreadTaskRunnerHandle::Get()),
+      locale_(locale),
+      install_update_if_possible_(install_update_if_possible),
+      elevation_window_(elevation_window),
+      delegate_(delegate),
+      system_level_install_(false),
+      last_reported_progress_(0),
+      status_(UPGRADE_ERROR),
       error_code_(GOOGLE_UPDATE_NO_ERROR),
       hresult_(S_OK),
-      job_observer_(nullptr) {
+      installer_exit_code_(-1) {
 }
 
 UpdateCheckDriver::~UpdateCheckDriver() {
   DCHECK(result_runner_->BelongsToCurrentThread());
   // If there is an error, then error_code must not be blank, and vice versa.
-  DCHECK_NE(result_ == UPGRADE_ERROR, error_code_ == GOOGLE_UPDATE_NO_ERROR);
-  UMA_HISTOGRAM_ENUMERATION("GoogleUpdate.UpgradeResult", result_,
-                            NUM_UPGRADE_RESULTS);
-  if (result_ == UPGRADE_ERROR) {
+  DCHECK_NE(status_ == UPGRADE_ERROR, error_code_ == GOOGLE_UPDATE_NO_ERROR);
+  UMA_HISTOGRAM_ENUMERATION("GoogleUpdate.UpgradeResult", status_,
+                            NUM_UPGRADE_STATUS);
+  if (status_ == UPGRADE_ERROR) {
     UMA_HISTOGRAM_ENUMERATION("GoogleUpdate.UpdateErrorCode", error_code_,
                               NUM_ERROR_CODES);
-    if (hresult_ != S_OK)
+    if (FAILED(hresult_))
       UMA_HISTOGRAM_SPARSE_SLOWLY("GoogleUpdate.ErrorHresult", hresult_);
-  }
-  result_callback_.Run(result_, error_code_, error_message_, version_);
-}
-
-void UpdateCheckDriver::BeginUpdateCheck(
-    bool install_if_newer,
-    gfx::AcceleratedWidget elevation_window) {
-  // Return results immediately if the driver is not waiting for Google Update.
-  if (!BeginUpdateCheckInternal(install_if_newer, elevation_window))
+    if (installer_exit_code_ != -1) {
+      UMA_HISTOGRAM_SPARSE_SLOWLY("GoogleUpdate.InstallerExitCode",
+                                  installer_exit_code_);
+    }
+  }
+  if (delegate_) {
+    if (status_ == UPGRADE_ERROR)
+      delegate_->OnError(error_code_, error_message_, new_version_);
+    else if (install_update_if_possible_)
+      delegate_->OnUpgradeComplete(new_version_);
+    else
+      delegate_->OnUpdateCheckComplete(new_version_);
+  }
+}
+
+void UpdateCheckDriver::BeginUpdateCheck() {
+  GoogleUpdateErrorCode error_code = GOOGLE_UPDATE_NO_ERROR;
+  HRESULT hresult = BeginUpdateCheckInternal(&error_code);
+  if (SUCCEEDED(hresult)) {
+    // Start polling.
+    task_runner_->PostTask(FROM_HERE,
+                           base::Bind(&UpdateCheckDriver::PollGoogleUpdate,
+                                      base::Unretained(this)));
+  } else {
+    // Return results immediately since the driver is not polling Google Update.
+    OnUpgradeError(error_code, hresult, -1, base::string16());
     result_runner_->DeleteSoon(FROM_HERE, this);
-}
-
-bool UpdateCheckDriver::BeginUpdateCheckInternal(
-    bool install_if_newer,
-    gfx::AcceleratedWidget elevation_window) {
+  }
+}
+
+HRESULT UpdateCheckDriver::BeginUpdateCheckInternal(
+    GoogleUpdateErrorCode* error_code) {
   base::FilePath chrome_exe;
   if (!PathService::Get(base::DIR_EXE, &chrome_exe))
     NOTREACHED();
 
-  const bool system_level = !InstallUtil::IsPerUserInstall(chrome_exe);
-
-  // The failures handled here are:
-  // CANNOT_UPGRADE_CHROME_IN_THIS_DIRECTORY,
-  // GOOGLE_UPDATE_DISABLED_BY_POLICY, and
-  // GOOGLE_UPDATE_DISABLED_BY_POLICY_AUTO_ONLY.
-  error_code_ = CanUpdateCurrentChrome(chrome_exe, system_level);
-  if (error_code_ != GOOGLE_UPDATE_NO_ERROR) {
-    // These failures are handled in the UX with custom messages.
-    result_ = UPGRADE_ERROR;
-    return false;
-  }
+  system_level_install_ = !InstallUtil::IsPerUserInstall(chrome_exe);
 
   // Make sure ATL is initialized in this module.
   ui::win::CreateATLModuleIfNeeded();
 
-  HRESULT hr =
-      CComObject<GoogleUpdateJobObserver>::CreateInstance(&job_observer_);
-  if (hr != S_OK) {
-    // Most of the error messages come straight from Google Update. This one is
-    // deemed worthy enough to also warrant its own error.
-    OnUpgradeError(GOOGLE_UPDATE_JOB_SERVER_CREATION_FAILED, hr, false);
+  *error_code = CanUpdateCurrentChrome(chrome_exe, system_level_install_);
+  if (*error_code != GOOGLE_UPDATE_NO_ERROR)
+    return E_FAIL;
+
+  HRESULT hresult = CreateGoogleUpdate3WebClass(
+      system_level_install_, install_update_if_possible_, elevation_window_,
+      &google_update_);
+  if (FAILED(hresult)) {
+    *error_code = GOOGLE_UPDATE_ONDEMAND_CLASS_NOT_FOUND;
+    return hresult;
+  }
+
+  // The class was created, so all subsequent errors are reported as:
+  *error_code = GOOGLE_UPDATE_ONDEMAND_CLASS_REPORTED_ERROR;
+  base::string16 app_guid =
+      installer::GetAppGuidForUpdates(system_level_install_);
+  DCHECK(!app_guid.empty());
+
+  {
+    base::win::ScopedComPtr<IDispatch> dispatch;
+    hresult = google_update_->createAppBundleWeb(dispatch.Receive());
+    if (FAILED(hresult))
+      return hresult;
+    hresult = dispatch.QueryInterface(app_bundle_.Receive());
+    if (FAILED(hresult))
+      return hresult;
+  }
+
+  if (!locale_.empty()) {
+    // Ignore the result of this since, while setting the display language is
+    // nice to have, a failure to do so does not affect the likelihood that the
+    // update check and/or install will succeed.
+    app_bundle_->put_displayLanguage(
+        base::win::ScopedBstr(base::UTF8ToUTF16(locale_).c_str()));
+  }
+
+  hresult = app_bundle_->initialize();
+  if (FAILED(hresult))
+    return hresult;
+  if (elevation_window_) {
+    // Likewise, a failure to set the parent window need not block an update
+    // check.
+    app_bundle_->put_parentHWND(reinterpret_cast<ULONG_PTR>(elevation_window_));
+  }
+
+  base::win::ScopedComPtr<IDispatch> dispatch;
+  hresult =
+      app_bundle_->createInstalledApp(base::win::ScopedBstr(app_guid.c_str()));
+  if (FAILED(hresult))
+    return hresult;
+  hresult = app_bundle_->get_appWeb(0, dispatch.Receive());
+  if (FAILED(hresult))
+    return hresult;
+  hresult = dispatch.QueryInterface(app_.Receive());
+  if (FAILED(hresult))
+    return hresult;
+  return app_bundle_->checkForUpdate();
+}
+
+bool UpdateCheckDriver::GetCurrentState(
+    base::win::ScopedComPtr<ICurrentState>* current_state,
+    CurrentState* state_value,
+    HRESULT* hresult) const {
+  base::win::ScopedComPtr<IDispatch> dispatch;
+  *hresult = app_->get_currentState(dispatch.Receive());
+  if (FAILED(*hresult))
     return false;
-  }
-  // Hold a reference on the observer for the lifetime of the driver.
-  job_holder_ = job_observer_;
-
-  job_observer_->set_on_complete_callback(base::Bind(
-      &UpdateCheckDriver::CompleteUpdateCheck, base::Unretained(this)));
-
-  hr = CreateOnDemandAppsClass(system_level, install_if_newer, elevation_window,
-                               &on_demand_);
-  if (hr != S_OK) {
-    OnUpgradeError(GOOGLE_UPDATE_ONDEMAND_CLASS_NOT_FOUND, hr, system_level);
+  *hresult = dispatch.QueryInterface(current_state->Receive());
+  if (FAILED(*hresult))
     return false;
-  }
-
-  base::string16 app_guid = installer::GetAppGuidForUpdates(system_level);
-  DCHECK(!app_guid.empty());
-
-  if (install_if_newer)
-    hr = on_demand_->Update(app_guid.c_str(), job_observer_);
-  else
-    hr = on_demand_->CheckForUpdate(app_guid.c_str(), job_observer_);
-
-  if (hr != S_OK) {
-    OnUpgradeError(GOOGLE_UPDATE_ONDEMAND_CLASS_REPORTED_ERROR, hr,
-                   system_level);
+  LONG value = 0;
+  *hresult = (*current_state)->get_stateValue(&value);
+  if (FAILED(*hresult))
     return false;
-  }
+  *state_value = static_cast<CurrentState>(value);
   return true;
 }
 
-void UpdateCheckDriver::CompleteUpdateCheck() {
-  result_ = job_observer_->result();
-  if (result_ == UPGRADE_ERROR) {
-    error_code_ = GOOGLE_UPDATE_ERROR_UPDATING;
-    error_message_ = job_observer_->error_message();
-  } else {
-    version_ = job_observer_->new_version();
+bool UpdateCheckDriver::IsErrorState(
+    const base::win::ScopedComPtr<ICurrentState>& current_state,
+    CurrentState state_value,
+    GoogleUpdateErrorCode* error_code,
+    HRESULT* hresult,
+    int* installer_exit_code,
+    base::string16* error_string) const {
+  if (state_value == STATE_ERROR) {
+    // In general, errors reported by Google Update fall under this category
+    // (see special case below).
+    *error_code = GOOGLE_UPDATE_ERROR_UPDATING;
+
+    // In general, the exit code of Chrome's installer is unknown (see special
+    // case below).
+    *installer_exit_code = -1;
+
+    // Report the error_code provided by Google Update if possible, or the
+    // reason it wasn't possible otherwise.
+    LONG long_value = 0;
+    *hresult = current_state->get_errorCode(&long_value);
+    if (SUCCEEDED(*hresult))
+      *hresult = long_value;
+
+    // Special cases:
+    // - Use a custom error code if Google Update repoted that the update was
+    //   disabled by a Group Policy setting.
+    // - Extract the exit code of Chrome's installer if Google Update repoted
+    //   that the update failed because of a failure in the installer.
+    LONG code = 0;
+    if (*hresult == GOOPDATE_E_APP_UPDATE_DISABLED_BY_POLICY) {
+      *error_code = GOOGLE_UPDATE_DISABLED_BY_POLICY;
+    } else if (*hresult == GOOPDATEINSTALL_E_INSTALLER_FAILED &&
+               SUCCEEDED(current_state->get_installerResultCode(&code))) {
+      *installer_exit_code = code;
+    }
+
+    base::win::ScopedBstr message;
+    if (SUCCEEDED(current_state->get_completionMessage(message.Receive())))
+      error_string->assign(message, message.Length());
+
+    return true;
+  }
+  if (state_value == STATE_UPDATE_AVAILABLE && install_update_if_possible_) {
+    *hresult = app_bundle_->install();

[S. Ganesh, 2015/05/13 20:21:41]

It is somewhat unexpected to see IsErrorState() calling install(). Perhaps have
another function (or) call it directly from PollGoogleUpdate().

[grt (UTC plus 2), 2015/05/13 20:36:38]

Understood. The reason it isn't called from PollGoogleUpdate is that I wanted to
minimize the paths that would end up calling OnUpgradeError.

+    if (FAILED(*hresult)) {
+      // Report a failure to start the install as a general error while trying
+      // to interact with Google Update.
+      *error_code = GOOGLE_UPDATE_ONDEMAND_CLASS_REPORTED_ERROR;
+      *installer_exit_code = -1;
+      return true;
+    }
+    // Return false for handling in IsIntermediateState.
+  }
+  return false;
+}
+
+bool UpdateCheckDriver::IsFinalState(
+    const base::win::ScopedComPtr<ICurrentState>& current_state,
+    CurrentState state_value,
+    GoogleUpdateUpgradeStatus* upgrade_status,
+    base::string16* new_version) const {
+  if (state_value == STATE_UPDATE_AVAILABLE && !install_update_if_possible_) {
+    base::win::ScopedBstr version;
+    *upgrade_status = UPGRADE_IS_AVAILABLE;
+    if (SUCCEEDED(current_state->get_availableVersion(version.Receive())))

[S. Ganesh, 2015/05/13 20:21:40]

Minor code duplication here and in IsIntermediateState(). Would it be possible
to call on IsIntermediateState() first, and then IsFinalState(), such that the
latter then only has to return "true" for the !install_update_if_possible_ case?

[grt (UTC plus 2), 2015/05/13 20:36:38]

It would be possible, but would take some rejiggering of the logic in
PollGoogleUpdate, which I think is fairly clear as-is.

+      new_version->assign(version, version.Length());
+    return true;
+  }
+  if (state_value == STATE_INSTALL_COMPLETE) {
+    DCHECK(install_update_if_possible_);
+    *upgrade_status = UPGRADE_SUCCESSFUL;
+    return true;
+  }
+  if (state_value == STATE_NO_UPDATE) {
+    *upgrade_status = UPGRADE_ALREADY_UP_TO_DATE;
+    return true;
+  }
+  return false;
+}
+
+bool UpdateCheckDriver::IsIntermediateState(
+    const base::win::ScopedComPtr<ICurrentState>& current_state,
+    CurrentState state_value,
+    base::string16* new_version,
+    int* progress) const {
+  // ERROR will have been handled in IsErrorState. UPDATE_AVAILABLE, and
+  // NO_UPDATE will have been handled in IsFinalState if not doing an install,
+  // as will STATE_INSTALL_COMPLETE when doing an install. All other states
+  // following UPDATE_AVAILABLE will only happen when an install is to be done.
+  DCHECK(state_value < STATE_UPDATE_AVAILABLE || install_update_if_possible_);
+  *progress = 0;
+
+  switch (state_value) {
+    case STATE_INIT:
+    case STATE_WAITING_TO_CHECK_FOR_UPDATE:
+    case STATE_CHECKING_FOR_UPDATE:
+      // There is no news to report yet.
+      break;
+
+    case STATE_UPDATE_AVAILABLE: {
+      base::win::ScopedBstr version;
+      if (SUCCEEDED(current_state->get_availableVersion(version.Receive())))
+        new_version->assign(version, version.Length());
+      break;
+    }
+
+    case STATE_WAITING_TO_DOWNLOAD:
+    case STATE_RETRYING_DOWNLOAD:
+      break;
+
+    case STATE_DOWNLOADING: {
+      ULONG bytes_downloaded = 0;
+      ULONG total_bytes = 0;
+      if (SUCCEEDED(current_state->get_bytesDownloaded(&bytes_downloaded)) &&
+          SUCCEEDED(current_state->get_totalBytesToDownload(&total_bytes)) &&
+          total_bytes) {
+        // 0-50 is downloading.
+        *progress = gfx::ToFlooredInt((static_cast<double>(bytes_downloaded) /
+                                       static_cast<double>(total_bytes)) *
+                                      50.0);
+      }
+      break;
+    }
+
+    case STATE_DOWNLOAD_COMPLETE:
+    case STATE_EXTRACTING:
+    case STATE_APPLYING_DIFFERENTIAL_PATCH:
+    case STATE_READY_TO_INSTALL:
+    case STATE_WAITING_TO_INSTALL:
+      *progress = 50;
+      break;
+
+    case STATE_INSTALLING: {
+      *progress = 50;
+      LONG install_progress = 0;
+      if (SUCCEEDED(current_state->get_installProgress(&install_progress)) &&
+          install_progress >= 0 && install_progress <= 100) {
+        // 50-100 is installing.
+        *progress = (50 + install_progress / 2);
+      }
+      break;
+    }
+
+    case STATE_INSTALL_COMPLETE:
+    case STATE_PAUSED:
+    case STATE_NO_UPDATE:
+    case STATE_ERROR:
+    default:
+      NOTREACHED();
+      UMA_HISTOGRAM_SPARSE_SLOWLY("GoogleUpdate.UnexpectedState", state_value);
+      return false;
+  }
+  return true;
+}
+
+void UpdateCheckDriver::PollGoogleUpdate() {
+  base::win::ScopedComPtr<ICurrentState> state;
+  CurrentState state_value = STATE_INIT;
+  HRESULT hresult = S_OK;
+  GoogleUpdateErrorCode error_code = GOOGLE_UPDATE_NO_ERROR;
+  int installer_exit_code = -1;
+  base::string16 error_string;
+  GoogleUpdateUpgradeStatus upgrade_status = UPGRADE_ERROR;
+  base::string16 new_version;
+  int progress = 0;
+
+  if (!GetCurrentState(&state, &state_value, &hresult)) {
+    OnUpgradeError(GOOGLE_UPDATE_ONDEMAND_CLASS_REPORTED_ERROR, hresult, -1,
+                   base::string16());
+  } else if (IsErrorState(state, state_value, &error_code, &hresult,
+                          &installer_exit_code, &error_string)) {
+    OnUpgradeError(error_code, hresult, installer_exit_code, error_string);
+  } else if (IsFinalState(state, state_value, &upgrade_status, &new_version)) {
+    status_ = upgrade_status;
+    error_code_ = GOOGLE_UPDATE_NO_ERROR;
+    error_message_.clear();
+    if (!new_version.empty())
+      new_version_ = new_version;
+    hresult_ = S_OK;
+    installer_exit_code_ = -1;
+  } else if (IsIntermediateState(state, state_value, &new_version, &progress)) {
+    bool got_new_version = new_version_.empty() && !new_version.empty();
+    if (got_new_version)
+      new_version_ = new_version;
+    // Give the caller this status update if it differs from the last one given.
+    if (got_new_version || progress != last_reported_progress_) {
+      last_reported_progress_ = progress;
+
+      // It is safe to post this task with an unretained pointer since the task
+      // is guaranteed to run before a subsequent DeleteSoon is handled.
+      result_runner_->PostTask(
+          FROM_HERE,
+          base::Bind(&UpdateCheckDelegate::OnUpgradeProgress, delegate_,
+                     last_reported_progress_, new_version_));
+    }
+
+    // Schedule the next check.
+    task_runner_->PostDelayedTask(
+        FROM_HERE, base::Bind(&UpdateCheckDriver::PollGoogleUpdate,
+                              base::Unretained(this)),
+        base::TimeDelta::FromMilliseconds(kGoogleUpdatePollIntervalMs));
+    // Early return for this non-terminal state.
+    return;
   }
 
   // Release the reference on the COM objects before bouncing back to the
   // caller's thread.
-  on_demand_.Release();
-  job_holder_.Release();
-  job_observer_ = nullptr;
+  state.Release();
+  app_.Release();
+  app_bundle_.Release();
+  google_update_.Release();
 
   result_runner_->DeleteSoon(FROM_HERE, this);
 }
 
 void UpdateCheckDriver::OnUpgradeError(GoogleUpdateErrorCode error_code,
-                                       HRESULT hr,
-                                       bool system_level) {
-  result_ = UPGRADE_ERROR;
+                                       HRESULT hresult,
+                                       int installer_exit_code,
+                                       const base::string16& error_string) {
+  status_ = UPGRADE_ERROR;
   error_code_ = error_code;
-  hresult_ = hr;
+  hresult_ = hresult;
+  installer_exit_code_ = installer_exit_code;
   base::string16 error_msg =
       base::StringPrintf(L"%d: 0x%x", error_code_, hresult_);
-  if (system_level)
+  if (installer_exit_code_ != -1)
+    error_msg += base::StringPrintf(L": %d", installer_exit_code_);
+  if (system_level_install_)
     error_msg += L" -- system level";
-  error_message_ = l10n_util::GetStringFUTF16(
-      IDS_ABOUT_BOX_ERROR_UPDATE_CHECK_FAILED, error_msg);
+  if (error_string.empty()) {
+    error_message_ = l10n_util::GetStringFUTF16(
+        IDS_ABOUT_BOX_ERROR_UPDATE_CHECK_FAILED, error_msg);
+  } else {
+    error_message_ = l10n_util::GetStringFUTF16(
+        IDS_ABOUT_BOX_GOOGLE_UPDATE_ERROR, error_string, error_msg);
+  }
 }
 
 }  // namespace
 
 
 // Globals ---------------------------------------------------------------------
 
-void BeginUpdateCheck(const scoped_refptr<base::TaskRunner>& task_runner,
-                      bool install_if_newer,
-                      gfx::AcceleratedWidget elevation_window,
-                      const UpdateCheckCallback& callback) {
-  UpdateCheckDriver::RunUpdateCheck(task_runner, install_if_newer,
-                                    elevation_window, callback);
+void BeginUpdateCheck(
+    const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+    const std::string& locale,
+    bool install_update_if_possible,
+    gfx::AcceleratedWidget elevation_window,
+    const base::WeakPtr<UpdateCheckDelegate>& delegate) {
+  UpdateCheckDriver::RunUpdateCheck(task_runner, locale,
+                                    install_update_if_possible,
+                                    elevation_window, delegate);
 }
 
 
 // Private API exposed for testing. --------------------------------------------
 
 void SetGoogleUpdateFactoryForTesting(
-    const OnDemandAppsClassFactory& google_update_factory) {
+    const GoogleUpdate3ClassFactory& google_update_factory) {
   if (g_google_update_factory) {
     delete g_google_update_factory;
     g_google_update_factory = nullptr;
   }
   if (!google_update_factory.is_null()) {
     g_google_update_factory =
-        new OnDemandAppsClassFactory(google_update_factory);
+        new GoogleUpdate3ClassFactory(google_update_factory);
   }
 }