Added a PolicyDomainDescriptor.

chrome/browser/policy/policy_domain_descriptor.cc

Index: chrome/browser/policy/policy_domain_descriptor.cc
diff --git a/chrome/browser/policy/policy_domain_descriptor.cc b/chrome/browser/policy/policy_domain_descriptor.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b268719717f59ffa0986945a724f1f16ddff713c
--- /dev/null
+++ b/chrome/browser/policy/policy_domain_descriptor.cc
@@ -0,0 +1,68 @@
+// Copyright (c) 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 "chrome/browser/policy/policy_domain_descriptor.h"
+
+#include "base/stl_util.h"
+#include "chrome/browser/policy/policy_bundle.h"
+#include "chrome/browser/policy/policy_map.h"
+#include "chrome/browser/policy/policy_schema.h"
+
+namespace policy {
+
+PolicyDomainDescriptor::PolicyDomainDescriptor(PolicyDomain domain)
+    : domain_(domain) {}
+
+void PolicyDomainDescriptor::AddComponent(const std::string& component_id,
+                                          scoped_ptr<PolicySchema> schema) {
+  const PolicySchema*& previous = schema_map_[component_id];
+  delete previous;
+  previous = schema.release();
+}
+
+void PolicyDomainDescriptor::FilterBundle(PolicyBundle* bundle) const {
+  for (PolicyBundle::const_iterator it_bundle = bundle->begin();
+       it_bundle != bundle->end(); ++it_bundle) {
+    const PolicyNamespace& ns = it_bundle->first;
+    if (ns.domain != domain_)
+      continue;
+
+    SchemaMap::const_iterator it_schema = schema_map_.find(ns.component_id);
+    if (it_schema == schema_map_.end()) {
+      // Component ID not found.
+      bundle->Get(ns).Clear();
+      continue;
+    }
+
+    // TODO(joaodasilva): if a component is registered but doesn't have a schema
+    // then its policies aren't filtered. This behavior is enabled for M29 to
+    // allow a graceful update of the Legacy Browser Support extension; it'll
+    // be removed for M30. http://crbug.com/240704

[Mattias Nissler (ping if slow), 2013/05/15 10:24:06]

Have you made sure that the extension gets updated well ahead of time?

[Joao da Silva, 2013/05/19 13:17:55]

Yes, I'm in sync with Julian here.

+    if (!it_schema->second)
+      continue;
+
+    const PolicySchema::TypeMap& type_map = it_schema->second->type_map();
+    PolicyMap& map = bundle->Get(ns);
+    PolicyMap::const_iterator it_map = map.begin();
+    while (it_map != map.end()) {
+      PolicySchema::TypeMap::const_iterator it_type =
+          type_map.find(it_map->first);

[Mattias Nissler (ping if slow), 2013/05/15 10:24:06]

Given these are both indexed by name, we might be able to just start at
type_map.begin() and advance it_type appropriately?

[Joao da Silva, 2013/05/19 13:17:55]

This has changed after the PolicySchema changes.

+      if (it_type == type_map.end() ||
+          !it_map->second.value ||
+          !it_map->second.value->IsType(it_type->second)) {
+        const std::string& name = it_map->first;
+        ++it_map;
+        map.Erase(name);
+      } else {
+        ++it_map;
+      }
+    }
+  }
+}
+
+PolicyDomainDescriptor::~PolicyDomainDescriptor() {
+  STLDeleteValues(&schema_map_);
+}
+
+}  // namespace policy