Update some uses of Value in chrome/browser to use the base:: namespace.

chrome/browser/policy/url_blacklist_policy_handler.cc

Index: chrome/browser/policy/url_blacklist_policy_handler.cc
diff --git a/chrome/browser/policy/url_blacklist_policy_handler.cc b/chrome/browser/policy/url_blacklist_policy_handler.cc
index 5bc2385caa3ac2e73e7582c3e622dcaaf3ecd3cb..8e51f90675ae57c502592f7e52df8f9fce140ac7 100644
--- a/chrome/browser/policy/url_blacklist_policy_handler.cc
+++ b/chrome/browser/policy/url_blacklist_policy_handler.cc
@@ -71,7 +71,7 @@ void URLBlacklistPolicyHandler::ApplyPolicySettings(const PolicyMap& policies,
   if (url_blacklist) {
     for (base::ListValue::const_iterator entry(url_blacklist->begin());
          entry != url_blacklist->end(); ++entry) {
-      if ((*entry)->IsType(Value::TYPE_STRING))
+      if ((*entry)->IsType(base::Value::TYPE_STRING))
         merged_url_blacklist->Append((*entry)->DeepCopy());
     }
   }