Purge cache when the server removes the policy for an extension.

components/policy/core/common/cloud/cloud_policy_client.cc

Index: components/policy/core/common/cloud/cloud_policy_client.cc
diff --git a/components/policy/core/common/cloud/cloud_policy_client.cc b/components/policy/core/common/cloud/cloud_policy_client.cc
index 3014fd7f1585755d8825c7c6ad01341d57aec0e5..fe2d2675a4458ebf17214d41904c2dea15bcbd84 100644
--- a/components/policy/core/common/cloud/cloud_policy_client.cc
+++ b/components/policy/core/common/cloud/cloud_policy_client.cc
@@ -220,7 +220,8 @@ void CloudPolicyClient::FetchPolicy() {
 
   // Fire the job.
   request_job_->Start(base::Bind(&CloudPolicyClient::OnPolicyFetchCompleted,
-                                 base::Unretained(this)));
+                                 base::Unretained(this),
+                                 namespaces_to_fetch_));
 }
 
 void CloudPolicyClient::FetchRobotAuthCodes(const std::string& auth_token) {
@@ -376,6 +377,7 @@ void CloudPolicyClient::OnFetchRobotAuthCodesCompleted(
 }
 
 void CloudPolicyClient::OnPolicyFetchCompleted(
+    const NamespaceSet& namespaces_requested,
     DeviceManagementStatus status,
     int net_error,
     const em::DeviceManagementResponse& response) {
@@ -389,9 +391,10 @@ void CloudPolicyClient::OnPolicyFetchCompleted(
 
   status_ = status;
   if (status == DM_STATUS_SUCCESS) {
+    namespaces_requested_ = namespaces_requested;
+    STLDeleteValues(&responses_);
     const em::DevicePolicyResponse& policy_response =
         response.policy_response();
-    STLDeleteValues(&responses_);
     for (int i = 0; i < policy_response.response_size(); ++i) {
       const em::PolicyFetchResponse& response = policy_response.response(i);
       em::PolicyData policy_data;