Add a NoStatePrefetch entry in about://flags

chrome/browser/prerender/prerender_field_trial.h

 // 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.
 
 #ifndef CHROME_BROWSER_PRERENDER_PRERENDER_FIELD_TRIAL_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_FIELD_TRIAL_H_
 
 #include "base/feature_list.h"
 
 class Profile;
 
 namespace prerender {
 
-// Exposed for testing.
 extern const base::Feature kNoStatePrefetchFeature;
 extern const char kNoStatePrefetchFeatureModeParameterName[];
+extern const char kNoStatePrefetchFeatureModeParameterPrefetch[];

[Alexei Svitkine (slow), 2016/12/07 15:50:00]

Is there a corresponding .cc file change missing from the CL?

[droger, 2016/12/07 15:55:30]

No, these constants already exist, they just were made public in this CL.

Note that they were not in anonymous namespace (as they should have been),
that's why there is no change needed to the cc file.

+extern const char kNoStatePrefetchFeatureModeParameterPrerender[];
 extern const char kNoStatePrefetchFeatureModeParameterSimpleLoad[];
 
 // Configures prerender using kNoStatePrefetchFeature and field trial
 // parameters.
 void ConfigurePrerender();
 
 // Returns true if the user has opted in or has been opted in to the
 // prerendering from Omnibox experiment.
 bool IsOmniboxEnabled(Profile* profile);
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_FIELD_TRIAL_H_