Added a PolicyDomainDescriptor.

chrome/browser/policy/async_policy_loader.h

Index: chrome/browser/policy/async_policy_loader.h
diff --git a/chrome/browser/policy/async_policy_loader.h b/chrome/browser/policy/async_policy_loader.h
index 61529e71b6e7d287c2d7e642fd75e92e2bce1f47..f21b920caacb46e4af780e37370f1b10bbaf5dee 100644
--- a/chrome/browser/policy/async_policy_loader.h
+++ b/chrome/browser/policy/async_policy_loader.h
@@ -5,10 +5,14 @@
 #ifndef CHROME_BROWSER_POLICY_ASYNC_POLICY_LOADER_H_
 #define CHROME_BROWSER_POLICY_ASYNC_POLICY_LOADER_H_
 
+#include <map>
+
 #include "base/callback.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time.h"
+#include "chrome/browser/policy/policy_domain_descriptor.h"
 
 namespace policy {
 
@@ -52,6 +56,21 @@ class AsyncPolicyLoader {
   // makes sure the policies are reloaded if the update events aren't triggered.
   void Reload(bool force);
 
+  // Passes the current |descriptor| for a domain, which is used to filter out
+  // policies that aren't registered, or whose type doesn't match the expected
+  // type.
+  void RegisterPolicyDomain(
+      scoped_refptr<const PolicyDomainDescriptor> descriptor);
+
+ protected:
+  typedef std::map<PolicyDomain, scoped_refptr<const PolicyDomainDescriptor> >
+      DescriptorMap;
+
+  // Returns the current DescriptorMap. This can be used by implementations to
+  // determine the components registered for each domain, and to filter out
+  // unknonwn policies.
+  const DescriptorMap& descriptor_map() const { return descriptor_map_; }
+
  private:
   // Allow AsyncPolicyProvider to call Init().
   friend class AsyncPolicyProvider;
@@ -90,6 +109,9 @@ class AsyncPolicyLoader {
   // non-local filesystem involved.
   base::Time last_modification_clock_;
 
+  // A map of the currently registered domains and their descriptors.
+  DescriptorMap descriptor_map_;
+
   DISALLOW_COPY_AND_ASSIGN(AsyncPolicyLoader);
 };