Add a policy to allow NTP promotions & default apps to be disabled.

chrome/browser/extensions/apps_promo.cc

 // Copyright (c) 2011 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/extensions/apps_promo.h"
 
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ skipping 43 matching lines @@
   // default apps for new users.
   prefs->RegisterIntegerPref(prefs::kAppsPromoCounter,
                              kDefaultAppsCounterMax + 1,
                              PrefService::UNSYNCABLE_PREF);
   prefs->RegisterBooleanPref(prefs::kDefaultAppsInstalled,
                              false,
                              PrefService::UNSYNCABLE_PREF);
   prefs->RegisterStringPref(prefs::kNTPWebStorePromoLastId,
                             std::string(),
                             PrefService::UNSYNCABLE_PREF);
+  prefs->RegisterBooleanPref(prefs::kNTPHideWebStorePromo,
+                            false,
+                            PrefService::UNSYNCABLE_PREF);
 }
 
 // static
 void AppsPromo::ClearPromo() {
   PrefService* local_state = g_browser_process->local_state();
   local_state->ClearPref(prefs::kNTPWebStoreEnabled);
   local_state->ClearPref(prefs::kNTPWebStorePromoId);
   local_state->ClearPref(prefs::kNTPWebStorePromoHeader);
   local_state->ClearPref(prefs::kNTPWebStorePromoButton);
   local_state->ClearPref(prefs::kNTPWebStorePromoLink);
@@ skipping 105 matching lines @@
 
 bool AppsPromo::ShouldShowPromo(const ExtensionIdSet& installed_ids,
                                 bool* just_expired) {
   *just_expired = false;
 
   if (CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kForceAppsPromoVisible)) {
     return true;
   }
 
+  // Don't show the promo if the policy says not to.
+  if (prefs_->GetBoolean(prefs::kNTPHideWebStorePromo)) {
+    ExpireDefaultApps();
+    return false;
+  }
+
   // Don't show the promo if one wasn't served to this locale.
   if (!IsPromoSupportedForLocale())
     return false;
 
   int promo_counter = GetPromoCounter();
   if (GetDefaultAppsInstalled() && promo_counter <= kDefaultAppsCounterMax) {
     // If the default apps were installed from a previous Chrome version, we
     // should still show the promo. If we don't have the exact set of default
     // apps, this means that the user manually installed or uninstalled one.
     // We no longer keep track of the default apps once others have been
     // installed, so expire them immediately.
     if (old_default_app_ids_ != installed_ids) {
       ExpireDefaultApps();
       return false;
     }
 
     if (promo_counter == kDefaultAppsCounterMax) {
       *just_expired = true;
 
       // The default apps have expired due to inaction, so ping PROMO_EXPIRE.
       UMA_HISTOGRAM_ENUMERATION(extension_misc::kAppsPromoHistogram,
                                 extension_misc::PROMO_EXPIRE,
                                 extension_misc::PROMO_BUCKET_BOUNDARY);
 
       ExpireDefaultApps();
-      return true;
     } else {
       SetPromoCounter(++promo_counter);
-      return true;
     }
+    return true;

[Evan Stade, 2011/08/09 19:54:55]

as long as you are changing the logic around, I think the clearest is:

if (!GetDefaultappsInstalled() || promo_counter > kDefaultAppsCounterMax)
  return installed_ids.empty();

[...]

return true;

   } else if (installed_ids.empty()) {
     return true;
   }
 
   return false;
 }
 
 bool AppsPromo::ShouldShowAppLauncher(const ExtensionIdSet& installed_ids) {
   // On Chrome OS the default apps are installed via a separate mechanism that
   // is always enabled. Therefore we always show the launcher.
-#if defined(OS_CHROME)
+#if defined(OS_CHROMEOS)
   return true;
 #else
 
   // Always show the app launcher if an app is installed.
   if (!installed_ids.empty())
     return true;
 
   // Otherwise, only show the app launcher if the web store is supported for the
   // current locale.
   return IsWebStoreSupportedForLocale();
@@ skipping 49 matching lines @@
 bool AppsPromo::GetDefaultAppsInstalled() const {
   return prefs_->GetBoolean(prefs::kDefaultAppsInstalled);
 }
 
 AppsPromo::UserGroup AppsPromo::GetCurrentUserGroup() const {
   const PrefService::Preference* last_promo_id
       = prefs_->FindPreference(prefs::kNTPWebStorePromoLastId);
   CHECK(last_promo_id);
   return last_promo_id->IsDefaultValue() ? USERS_NEW : USERS_EXISTING;
 }