Add a preference to control Windows desktop search redirection.

components/search_engines/desktop_search_win.cc

Index: components/search_engines/desktop_search_win.cc
diff --git a/components/search_engines/detect_desktop_search_win.cc b/components/search_engines/desktop_search_win.cc
similarity index 55%
rename from components/search_engines/detect_desktop_search_win.cc
rename to components/search_engines/desktop_search_win.cc
index 563e80de7f16d668065bbfb24ea25e68aef1cadf..16d7f92ee6aefdf000a1e9807cab085261c86271 100644
--- a/components/search_engines/detect_desktop_search_win.cc
+++ b/components/search_engines/desktop_search_win.cc
@@ -2,17 +2,56 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "components/search_engines/detect_desktop_search_win.h"
+#include "components/search_engines/desktop_search_win.h"
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
+#include "base/prefs/pref_service.h"
 #include "base/strings/string_util.h"
+#include "components/pref_registry/pref_registry_syncable.h"
 #include "components/search_engines/prepopulated_engines.h"
 #include "components/search_engines/template_url.h"
 #include "components/search_engines/template_url_prepopulate_data.h"
 #include "net/base/url_util.h"
 
+namespace {
+// Name of the Windows desktop search redirection preference.
+const char kWindowsDesktopSearchRedirectionPref[] =
+    "windows_desktop_search_redirection";
+}  // namespace
+
+const base::Feature kWindowsDesktopSearchRedirectionFeature = {

[Peter Kasting, 2015/12/01 02:23:05]

Nit: If you remove the .h declaration, you can declare this in
WindowsDesktopSearchRedirectionFeatureIsEnabled().

[fdoray, 2015/12/02 17:28:27]

See other comment. It needs to be declared in the header file so that it can be
referenced from about_flags.cc

+    "WindowsDesktopSearchRedirection", base::FEATURE_DISABLED_BY_DEFAULT
+};
+
+void RegisterWindowsDesktopSearchRedirectionPref(
+    user_prefs::PrefRegistrySyncable* registry) {
+  registry->RegisterBooleanPref(kWindowsDesktopSearchRedirectionPref, false);
+}
+
+WindowsDesktopSearchRedirectionPref GetWindowsDesktopSearchRedirectionPref(
+    PrefService* pref_service) {
+  const PrefService::Preference* preference =
+      pref_service->FindPreference(kWindowsDesktopSearchRedirectionPref);
+  DCHECK(preference);
+  if (preference->IsDefaultValue())
+    return WindowsDesktopSearchRedirectionPref::UNSET;
+
+  bool pref_value = false;
+  const bool has_boolean_value =
+      preference->GetValue()->GetAsBoolean(&pref_value);
+  DCHECK(has_boolean_value);
+
+  if (pref_value)
+    return WindowsDesktopSearchRedirectionPref::ENABLED;
+  return WindowsDesktopSearchRedirectionPref::DISABLED;

[Peter Kasting, 2015/12/01 02:23:05]

Nit: Simpler:

  return pref_value ? WindowsDesktopSearchRedirectionPref::ENABLED
                    : WindowsDesktopSearchRedirectionPref::DISABLED;

[fdoray, 2015/12/02 17:28:27]

This code is gone now.

+}
+
+bool WindowsDesktopSearchRedirectionFeatureIsEnabled() {
+  return base::FeatureList::IsEnabled(kWindowsDesktopSearchRedirectionFeature);
+}
+
 bool DetectWindowsDesktopSearch(const GURL& url,
                                 const SearchTermsData& search_terms_data,
                                 base::string16* search_terms) {