Introduce a separate preference for 'proxy server mode'

chrome/browser/policy/configuration_policy_store_interface.h

Index: chrome/browser/policy/configuration_policy_store_interface.h
diff --git a/chrome/browser/policy/configuration_policy_store_interface.h b/chrome/browser/policy/configuration_policy_store_interface.h
index 00ebf30adb8894a8a20d68656f045eebdbbc0bf9..b3d604a3b23d3223da139f164720aa894d4cb434 100644
--- a/chrome/browser/policy/configuration_policy_store_interface.h
+++ b/chrome/browser/policy/configuration_policy_store_interface.h
@@ -25,7 +25,7 @@ enum ConfigurationPolicyType {
   kPolicyDefaultSearchProviderIconURL,
   kPolicyDefaultSearchProviderEncodings,
   kPolicyDisableSpdy,
-  kPolicyProxyServerMode,
+  kPolicyProxyMode,
   kPolicyProxyServer,
   kPolicyProxyPacUrl,
   kPolicyProxyBypassList,
@@ -69,10 +69,24 @@ enum ConfigurationPolicyType {
   kPolicyDisable3DAPIs
 };
 
-static const int kPolicyNoProxyServerMode = 0;
-static const int kPolicyAutoDetectProxyMode = 1;
-static const int kPolicyManuallyConfiguredProxyMode = 2;
-static const int kPolicyUseSystemProxyMode = 3;
+
+// Constants for the "Proxy Server Mode" defined in the policies.
+// Note that these diverge from internal presentation defined in
+// ProxyPrefs::ProxyMode for legacy reasons. The following four
+// PolicyProxyModeType types were not very precise and had overlapping use
+// cases.
+enum PolicyProxyModeType {
+  // Disable Proxy, connect directly.
+  kPolicyNoProxyServerMode = 0,
+  // Auto detect proxy or use specific PAC script if given.
+  kPolicyAutoDetectProxyMode = 1,
+  // Use manually configured proxy servers (fixed servers).
+  kPolicyManuallyConfiguredProxyMode = 2,
+  // Use system proxy server.
+  kPolicyUseSystemProxyMode = 3,
+
+  kPolicyNumberOfProxyModes
+};
 
 // An abstract super class for policy stores that provides a method that can be
 // called by a |ConfigurationPolicyProvider| to specify a policy.