Move app_launcher.* out of chrome/browser/extensions and into apps/

This change also moves some UI code from chrome/browser/extensions into
/chrome/browser/ui/, and cleans up the app_launcher.* code.

BUG=159366


Review URL: https://chromiumcodereview.appspot.com/12095052

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@181875 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 233 insertions, 1 deletions

diff --git a/apps/DEPS b/apps/DEPS
index 980e672..0fc9ed2 100644
--- a/apps/DEPS
+++ b/apps/DEPS
@@ -2,9 +2,13 @@ include_rules = [
   "+base",
   "+content",
   # Temporary allowed includes.
-  # TODO(benwells): remove these.
+  # TODO(benwells): remove these (http://crbug.com/159366)
+  "+chrome/browser/browser_process.h",
   "+chrome/browser/extensions",
+  "+chrome/browser/prefs",
   "+chrome/browser/profiles",
   "+chrome/common/chrome_notification_types.h",
+  "+chrome/common/chrome_switches.h",
   "+chrome/common/extensions",
+  "+chrome/installer",
 ]
diff --git a/apps/app_launcher.cc b/apps/app_launcher.cc
new file mode 100644
index 0000000..73011bc
--- /dev/null
+++ b/apps/app_launcher.cc
@@ -0,0 +1,107 @@
+// Copyright 2013 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 "apps/app_launcher.h"
+
+#include "apps/pref_names.h"
+#include "base/command_line.h"
+#include "base/prefs/pref_registry_simple.h"
+#include "base/prefs/pref_service.h"
+#include "base/threading/sequenced_worker_pool.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/common/chrome_switches.h"
+#include "content/public/browser/browser_thread.h"
+
+#if defined(OS_WIN)
+#include "chrome/installer/launcher_support/chrome_launcher_support.h"
+#include "chrome/installer/util/browser_distribution.h"
+#endif
+
+namespace apps {
+
+namespace {
+
+enum AppLauncherState {
+  APP_LAUNCHER_UNKNOWN,
+  APP_LAUNCHER_ENABLED,
+  APP_LAUNCHER_DISABLED,
+};
+
+AppLauncherState SynchronousAppLauncherChecks() {
+#if defined(USE_ASH)
+  return APP_LAUNCHER_ENABLED;
+#elif !defined(OS_WIN)
+  return APP_LAUNCHER_DISABLED;
+#else
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kShowAppListShortcut)) {
+    return APP_LAUNCHER_ENABLED;
+  }
+
+  if (!BrowserDistribution::GetDistribution()->AppHostIsSupported())
+    return APP_LAUNCHER_DISABLED;
+
+  return APP_LAUNCHER_UNKNOWN;
+#endif
+}
+
+#if defined(OS_WIN)
+void UpdatePrefAndCallCallbackOnUI(
+    bool result,
+    const OnAppLauncherEnabledCompleted& completion_callback) {
+  PrefService* prefs = g_browser_process->local_state();
+  prefs->SetBoolean(prefs::kAppLauncherIsEnabled, result);
+  completion_callback.Run(result);
+}
+
+void IsAppLauncherInstalledOnBlockingPool(
+    const OnAppLauncherEnabledCompleted& completion_callback) {
+  DCHECK(content::BrowserThread::GetBlockingPool()->RunsTasksOnCurrentThread());
+  bool result = chrome_launcher_support::IsAppLauncherPresent();
+  content::BrowserThread::PostTask(content::BrowserThread::UI, FROM_HERE,
+      base::Bind(UpdatePrefAndCallCallbackOnUI, result, completion_callback));
+}
+#endif
+
+}  // namespace
+
+bool MaybeIsAppLauncherEnabled() {
+  return SynchronousAppLauncherChecks() == APP_LAUNCHER_ENABLED;
+}
+
+void GetIsAppLauncherEnabled(
+    const OnAppLauncherEnabledCompleted& completion_callback) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+
+  AppLauncherState state = SynchronousAppLauncherChecks();
+
+  if (state != APP_LAUNCHER_UNKNOWN) {
+    bool is_enabled = state == APP_LAUNCHER_ENABLED;
+    PrefService* prefs = g_browser_process->local_state();
+    prefs->SetBoolean(prefs::kAppLauncherIsEnabled, is_enabled);
+    completion_callback.Run(is_enabled);
+    return;
+  }
+
+#if defined(OS_WIN)
+  content::BrowserThread::PostBlockingPoolTask(
+      FROM_HERE,
+      base::Bind(&IsAppLauncherInstalledOnBlockingPool,
+                 completion_callback));
+#else
+  // SynchronousAppLauncherChecks() never returns APP_LAUNCHER_UNKNOWN on
+  // !defined(OS_WIN), so this path is never reached.
+  NOTREACHED();
+#endif
+}
+
+bool WasAppLauncherEnabled() {
+  PrefService* prefs = g_browser_process->local_state();
+  // In some tests, the prefs aren't initialised.
+  if (!prefs)
+    return SynchronousAppLauncherChecks() == APP_LAUNCHER_ENABLED;
+  return prefs->GetBoolean(prefs::kAppLauncherIsEnabled);
+}
+
+}  // namespace apps
diff --git a/apps/app_launcher.h b/apps/app_launcher.h
new file mode 100644
index 0000000..b6bbed3
--- /dev/null
+++ b/apps/app_launcher.h
@@ -0,0 +1,38 @@
+// Copyright 2013 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.
+
+#ifndef CHROME_APPS_APP_LAUNCHER_H_
+#define CHROME_APPS_APP_LAUNCHER_H_
+
+#include "base/basictypes.h"
+#include "base/callback_forward.h"
+
+class PrefRegistrySimple;
+
+namespace apps {
+
+// Called on the UI thread after determining if the launcher is enabled. A
+// boolean flag is passed, which is true if the app launcher is enabled.
+typedef base::Callback<void(bool)> OnAppLauncherEnabledCompleted;
+
+// A synchronous check to determine if the app launcher is enabled. If the
+// registry needs to be determined to find an accurate answer, this function
+// will NOT do so; instead if will default to false (the app launcher is not
+// enabled).
+// This function does not use the cached preference of whether the launcher
+// was enabled or not.
+bool MaybeIsAppLauncherEnabled();
+
+// Determine whether the app launcher is enabled or not. This may involve a trip
+// to a blocking thread. |completion_callback| is called when an answer is
+// ready. This needs to be called on the UI thread.
+void GetIsAppLauncherEnabled(
+    const OnAppLauncherEnabledCompleted& completion_callback);
+
+// Returns whether the app launcher was enabled the last time it was checked.
+bool WasAppLauncherEnabled();
+
+}  // namespace extensions
+
+#endif  // CHROME_APPS_APP_LAUNCHER_H_
diff --git a/apps/apps.gypi b/apps/apps.gypi
index 43f9cc5..257195d 100644
--- a/apps/apps.gypi
+++ b/apps/apps.gypi
@@ -22,10 +22,16 @@
         '<(INTERMEDIATE_DIR)',
       ],
       'sources': [
+        'app_launcher.cc',
+        'app_launcher.h',
         'app_restore_service.cc',
         'app_restore_service.h',
         'app_restore_service_factory.cc',
         'app_restore_service_factory.h',
+        'pref_names.cc',
+        'pref_names.h',
+        'prefs.cc',
+        'prefs.h',
       ],
       'conditions': [
         ['enable_extensions==0', {
diff --git a/apps/pref_names.cc b/apps/pref_names.cc
new file mode 100644
index 0000000..15a33f9
--- /dev/null
+++ b/apps/pref_names.cc
@@ -0,0 +1,17 @@
+// Copyright 2013 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 "apps/pref_names.h"
+
+namespace apps {
+
+namespace prefs {
+
+// Local state caching knowledge of whether the app launcher is installed.
+const char kAppLauncherIsEnabled[] =
+    "apps.app_launcher.should_show_apps_page";
+
+}  // namespace prefs
+
+}  // namespace apps
diff --git a/apps/pref_names.h b/apps/pref_names.h
new file mode 100644
index 0000000..1cca82f
--- /dev/null
+++ b/apps/pref_names.h
@@ -0,0 +1,18 @@
+// Copyright 2013 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.
+
+#ifndef APPS_PREF_NAMES_H_
+#define APPS_PREF_NAMES_H_
+
+namespace apps {
+
+namespace prefs {
+
+extern const char kAppLauncherIsEnabled[];
+
+}  // namespace prefs
+
+}  // namespace apps
+
+#endif  // APPS_PREF_NAMES_H_
diff --git a/apps/prefs.cc b/apps/prefs.cc
new file mode 100644
index 0000000..b883fbb
--- /dev/null
+++ b/apps/prefs.cc
@@ -0,0 +1,25 @@
+// Copyright 2013 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 "apps/prefs.h"
+
+#include "apps/app_launcher.h"
+#include "apps/pref_names.h"
+#include "base/prefs/pref_registry_simple.h"
+
+namespace apps {
+
+void RegisterPrefs(PrefRegistrySimple* registry) {
+  // This pref is a cache of the value from the registry the last time it was
+  // checked.
+  //
+  // During the pref initialization, if it is impossible to synchronously
+  // determine whether the app launcher is enabled, assume it is disabled.
+  // Anything that needs to know the absolute truth should call
+  // GetIsAppLauncherEnabled().
+  registry->RegisterBooleanPref(prefs::kAppLauncherIsEnabled,
+                                MaybeIsAppLauncherEnabled());
+}
+
+}  // namespace apps
diff --git a/apps/prefs.h b/apps/prefs.h
new file mode 100644
index 0000000..3734860
--- /dev/null
+++ b/apps/prefs.h
@@ -0,0 +1,17 @@
+// Copyright 2013 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.
+
+#ifndef APPS_PREFS_H_
+#define APPS_PREFS_H_
+
+class PrefRegistrySimple;
+
+namespace apps {
+
+// Register preferences for the apps system.
+void RegisterPrefs(PrefRegistrySimple* registry);
+
+}  // namespace apps
+
+#endif  // APPS_PREFS_H_