Add recommended extension installation support

extensions/browser/management_policy.cc

 // 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 "extensions/browser/management_policy.h"
 
 namespace extensions {
 
 namespace {
 
@@ skipping 29 matching lines @@
   return false;
 }
 
 bool ManagementPolicy::Provider::MustRemainDisabled(
     const Extension* extension,
     Extension::DisableReason* reason,
     base::string16* error) const {
   return false;
 }
 
+bool ManagementPolicy::Provider::MustRemainInstalled(
+    const Extension* extension,
+    base::string16* error) const {
+  return false;
+}
+
 void ManagementPolicy::RegisterProvider(Provider* provider) {
   providers_.insert(provider);
 }
 
 void ManagementPolicy::UnregisterProvider(Provider* provider) {
   providers_.erase(provider);
 }
 
 bool ManagementPolicy::UserMayLoad(const Extension* extension,
                                    base::string16* error) const {
-  return ApplyToProviderList(&Provider::UserMayLoad, "Installation",
-                             true, extension, error);
+  return ApplyToProviderList(
+      &Provider::UserMayLoad, "Installation", true, extension, error);
 }
 
 bool ManagementPolicy::UserMayModifySettings(const Extension* extension,
                                              base::string16* error) const {
-  return ApplyToProviderList(&Provider::UserMayModifySettings, "Modification",
-                             true, extension, error);
+  return ApplyToProviderList(
+      &Provider::UserMayModifySettings, "Modification", true, extension, error);
 }
 
 bool ManagementPolicy::MustRemainEnabled(const Extension* extension,
                                          base::string16* error) const {
-  return ApplyToProviderList(&Provider::MustRemainEnabled, "Disabling",
-                             false, extension, error);
+  return ApplyToProviderList(
+      &Provider::MustRemainEnabled, "Disabling", false, extension, error);
 }
 
 bool ManagementPolicy::MustRemainDisabled(const Extension* extension,
                                           Extension::DisableReason* reason,
                                           base::string16* error) const {
   for (ProviderList::const_iterator it = providers_.begin();
        it != providers_.end(); ++it)
     if ((*it)->MustRemainDisabled(extension, reason, error))
       return true;
 
   return false;
 }
 
+bool ManagementPolicy::MustRemainInstalled(const Extension* extension,
+                                           base::string16* error) const {
+  return ApplyToProviderList(
+      &Provider::MustRemainInstalled, "Removing", false, extension, error);
+}
+
 void ManagementPolicy::UnregisterAllProviders() {
   providers_.clear();
 }
 
 int ManagementPolicy::GetNumProviders() const {
   return providers_.size();
 }
 
 bool ManagementPolicy::ApplyToProviderList(ProviderFunction function,
                                            const char* debug_operation_name,
@@ skipping 11 matching lines @@
       DVLOG(1) << debug_operation_name << " of extension " << name
                << " (" << id << ")"
                << " prohibited by " << provider->GetDebugPolicyProviderName();
       return !normal_result;
     }
   }
   return normal_result;
 }
 
 }  // namespace extensions