Introduce a separate preference for 'proxy server mode'

chrome/browser/prefs/proxy_prefs.cc

Index: chrome/browser/prefs/proxy_prefs.cc
diff --git a/chrome/browser/prefs/proxy_prefs.cc b/chrome/browser/prefs/proxy_prefs.cc
new file mode 100644
index 0000000000000000000000000000000000000000..6b5a51f596e114528016b3eb04643b576fc206f7
--- /dev/null
+++ b/chrome/browser/prefs/proxy_prefs.cc
@@ -0,0 +1,45 @@
+// Copyright (c) 2010 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/prefs/proxy_prefs.h"
+
+#include "base/basictypes.h"
+#include "base/logging.h"
+
+namespace {
+
+// These names are exposed to the proxy extension API. They must be in sync
+// with the constants of ProxyPrefs.
+const char* kProxyModeNames[] = { "disabled",
+                                  "auto_detect",
+                                  "pac_script",
+                                  "fixed_servers",
+                                  "system" };
+
+}  // namespace
+
+namespace ProxyPrefs {
+
+COMPILE_ASSERT(arraysize(kProxyModeNames) == NUM_MODES,
+               kProxyModeNames_must_have_size_of_NUM_MODES);
+
+bool IntToProxyMode(int in_value, ProxyMode* out_value) {
+  DCHECK(out_value);
+  if (in_value < 0 || in_value >= NUM_MODES)
+    return false;
+  *out_value = static_cast<ProxyMode>(in_value);
+  return true;
+}
+
+// static
+bool StringToProxyMode(const std::string& in_value, ProxyMode* out_value) {
+  DCHECK(out_value);
+  for (int i = 0; i < NUM_MODES; i++) {
+    if (in_value == kProxyModeNames[i])
+      return IntToProxyMode(i, out_value);
+  }
+  return false;
+}
+
+}  // namespace