Control zero suggest with a pref, not a switch.

chrome/browser/ui/webui/instant_ui.cc

 // Copyright (c) 2012 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/ui/webui/instant_ui.h"
 
 #include "base/bind.h"
+#include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/webui/chrome_web_ui_data_source.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/web_ui.h"
 #include "content/public/browser/web_ui_message_handler.h"
 #include "grit/browser_resources.h"
 
 namespace {
 
@@ skipping 50 matching lines @@
   web_ui()->RegisterMessageCallback(
       "setPreferenceValue",
       base::Bind(&InstantUIMessageHandler::SetPreferenceValue,
                  base::Unretained(this)));
 }
 
 void InstantUIMessageHandler::GetPreferenceValue(const base::ListValue* args) {
   std::string pref_name;
   if (!args->GetString(0, &pref_name)) return;
 
-  double value = 0.0;
+  base::StringValue pref_name_value(pref_name);
+  if (pref_name == prefs::kInstantAnimationScaleFactor) {
+    double value = 0.0;
 #if defined(TOOLKIT_VIEWS)
-  if (pref_name == prefs::kInstantAnimationScaleFactor)
     value = slow_animation_scale_factor_;
 #endif
-
-  base::StringValue arg1(pref_name);
-  base::FundamentalValue arg2(value);
-  web_ui()->CallJavascriptFunction(
-      "instantConfig.getPreferenceValueResult",
-      arg1,
-      arg2);
+    web_ui()->CallJavascriptFunction(
+        "instantConfig.getPreferenceValueResult",
+        pref_name_value,
+        base::FundamentalValue(value));
+  } else if (pref_name == prefs::kExperimentalZeroSuggestUrlPrefix) {
+    PrefService* prefs = Profile::FromWebUI(web_ui())->GetPrefs();
+    web_ui()->CallJavascriptFunction(
+        "instantConfig.getPreferenceValueResult",
+        pref_name_value,
+        base::StringValue(prefs->GetString(pref_name.c_str())));
+  }
 }
 
 void InstantUIMessageHandler::SetPreferenceValue(const base::ListValue* args) {
   std::string pref_name;
   if (!args->GetString(0, &pref_name)) return;
 
-  double value;
-  if (!args->GetDouble(1, &value)) return;
-
+  if (pref_name == prefs::kInstantAnimationScaleFactor) {
+    double value;
+    if (!args->GetDouble(1, &value)) return;
 #if defined(TOOLKIT_VIEWS)
-  if (pref_name == prefs::kInstantAnimationScaleFactor) {
     // Clamp to something reasonable.
     value = std::max(0.1, std::min(value, 10.0));
     slow_animation_scale_factor_ = static_cast<int>(value);
+#else
+    NOTIMPLEMENTED();
+#endif
+  } else if (pref_name == prefs::kExperimentalZeroSuggestUrlPrefix) {
+    std::string value;
+    if (!args->GetString(1, &value)) return;
+    PrefService* prefs = Profile::FromWebUI(web_ui())->GetPrefs();
+    prefs->SetString(pref_name.c_str(), value);
   }
-#else
-  NOTIMPLEMENTED();
-#endif
 }
 
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
 // InstantUI
 
 InstantUI::InstantUI(content::WebUI* web_ui) : WebUIController(web_ui) {
   web_ui->AddMessageHandler(new InstantUIMessageHandler());
 
   // Set up the chrome://instant/ source.
   Profile* profile = Profile::FromWebUI(web_ui);
   ChromeURLDataManager::AddDataSource(profile, CreateInstantHTMLSource());
 }
 
 // static
 int InstantUI::GetSlowAnimationScaleFactor() {
   return InstantUIMessageHandler::slow_animation_scale_factor();
 }