[Cleanup] Remove some expired omnibox field trials.

components/omnibox/browser/omnibox_field_trial.h

 // Copyright 2014 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 COMPONENTS_OMNIBOX_BROWSER_OMNIBOX_FIELD_TRIAL_H_
 #define COMPONENTS_OMNIBOX_BROWSER_OMNIBOX_FIELD_TRIAL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 93 matching lines @@
 
   // Do not change these values as they need to be in sync with values
   // specified in experiment configs on the variations server.
   enum EmphasizeTitlesCondition {
     EMPHASIZE_WHEN_NONEMPTY = 0,
     EMPHASIZE_WHEN_TITLE_MATCHES = 1,
     EMPHASIZE_WHEN_ONLY_TITLE_MATCHES = 2,
     EMPHASIZE_NEVER = 3
   };
 
-  // Activates all dynamic field trials.  The main difference between
-  // the autocomplete dynamic and static field trials is that the former
-  // don't require any code changes on the Chrome side as they are controlled
-  // on the server side.  Chrome binary simply propagates all necessary
-  // information through the X-Client-Data header.
-  // This method may be called multiple times.
-  static void ActivateDynamicTrials();
-
   // ---------------------------------------------------------
   // For any experiment that's part of the bundled omnibox field trial.
 
   // Returns a bitmap containing AutocompleteProvider::Type values
   // that should be disabled in AutocompleteController.
   static int GetDisabledProviderTypes();
 
   // Returns whether the user is in any dynamic field trial where the
   // group has a the prefix |group_prefix|.
   static bool HasDynamicFieldTrialGroupPrefix(const char *group_prefix);
@@ skipping 323 matching lines @@
   // prioritize different wildcard contexts, see the implementation.  How to
   // interpret the value is left to the caller; this is rule-dependent.
   static std::string GetValueForRuleInContext(
       const std::string& rule,
       metrics::OmniboxEventProto::PageClassification page_classification);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(OmniboxFieldTrial);
 };
 
 #endif  // COMPONENTS_OMNIBOX_BROWSER_OMNIBOX_FIELD_TRIAL_H_