Serve fast NTP when experiment is enabled

chrome/browser/search/local_ntp_source.cc

Index: chrome/browser/search/local_ntp_source.cc
diff --git a/chrome/browser/search/local_ntp_source.cc b/chrome/browser/search/local_ntp_source.cc
index b4b4d7db944f5f21fe759cdeb8f350148e2e2164..b3eb45673e81ef420c8ef83a3720a98371bd84d3 100644
--- a/chrome/browser/search/local_ntp_source.cc
+++ b/chrome/browser/search/local_ntp_source.cc
@@ -8,6 +8,7 @@
 #include "base/logging.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/metrics/field_trial.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
@@ -78,6 +79,18 @@ bool DefaultSearchProviderIsGoogle(Profile* profile) {
        SEARCH_ENGINE_GOOGLE);
 }
 
+bool IsLocalNTPFastEnabled() {

[Mathieu, 2015/03/14 19:58:27]

Can you 1-line comment these functions?

[fserb, 2015/03/16 19:52:27]

Done.

+  return StartsWithASCII(base::FieldTrialList::FindFullName("LocalNTPFast"),
+                         "Enabled", true);
+}
+
+void SendResource(int resource_id,
+                  const content::URLDataSource::GotDataCallback& callback) {
+  scoped_refptr<base::RefCountedStaticMemory> response(
+      ResourceBundle::GetSharedInstance().LoadDataResourceBytes(resource_id));
+  callback.Run(response.get());
+}
+
 // Adds a localized string keyed by resource id to the dictionary.
 void AddString(base::DictionaryValue* dictionary,
                const std::string& key,
@@ -165,6 +178,15 @@ void LocalNtpSource::StartDataRequest(
     callback.Run(base::RefCountedString::TakeString(&config_data_js));
     return;
   }
+  if (IsLocalNTPFastEnabled()) {
+    if (stripped_path == "local-ntp.html") {
+      return SendResource(IDR_LOCAL_NTP_FAST_HTML, callback);
+    } else if (stripped_path == "local-ntp.js") {
+      return SendResource(IDR_LOCAL_NTP_FAST_JS, callback);
+    } else if (stripped_path == "local-ntp.css") {
+      return SendResource(IDR_LOCAL_NTP_FAST_CSS, callback);
+    }
+  }
   float scale = 1.0f;
   std::string filename;
   webui::ParsePathAndScale(