[TTS] Add server control from a field_trial param.

chrome/browser/android/contextualsearch/contextual_search_field_trial.cc

 // Copyright 2016 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/android/contextualsearch/contextual_search_field_trial.h"
 
 #include "base/command_line.h"
 #include "base/strings/string_number_conversions.h"
 #include "chrome/common/chrome_switches.h"
 #include "components/variations/variations_associated_data.h"
 
 namespace {
 
 const char kContextualSearchFieldTrialName[] = "ContextualSearch";
 const char kFalseValue[] = "false";
 const char kAnyNonEmptyValue[] = "1";
 const char kContextualSearchResolverUrl[] = "contextual-search-resolver-url";
 const char kContextualSearchSurroundingSizeParamName[] = "surrounding_size";
 const char kContextualSearchIcingSurroundingSizeParamName[] =
     "icing_surrounding_size";
 const char kContextualSearchSendURLDisabledParamName[] = "disable_send_url";
 const char kContextualSearchDecodeMentionsDisabledParamName[] =
     "disable_decode_mentions";
+const char kContextualCardsVersionParamName[] = "contextual_cards_version";
+
 // The default size of the content surrounding the selection to gather, allowing
 // room for other parameters.
 const int kContextualSearchDefaultContentSize = 1536;
 
 }  // namespace
 
 // static
 const int
     ContextualSearchFieldTrial::kContextualSearchDefaultIcingSurroundingSize =
         400;
 
 ContextualSearchFieldTrial::ContextualSearchFieldTrial()
     : is_resolver_url_prefix_cached_(false),
       is_surrounding_size_cached_(false),
       surrounding_size_(0),
       is_icing_surrounding_size_cached_(false),
       icing_surrounding_size_(0),
       is_send_base_page_url_disabled_cached_(false),
       is_send_base_page_url_disabled_(false),
       is_decode_mentions_disabled_cached_(false),
       is_decode_mentions_disabled_(false),
       is_contextual_cards_bar_integration_enabled_cached_(false),
-      is_contextual_cards_bar_integration_enabled_(false) {}
+      is_contextual_cards_bar_integration_enabled_(false),
+      is_contextual_cards_version_cached_(false),
+      contextual_cards_version_(0) {}
 
 ContextualSearchFieldTrial::~ContextualSearchFieldTrial() {}
 
 std::string ContextualSearchFieldTrial::GetResolverURLPrefix() {
   if (!is_resolver_url_prefix_cached_) {
     is_resolver_url_prefix_cached_ = true;
     resolver_url_prefix_ = GetSwitch(kContextualSearchResolverUrl);
     if (resolver_url_prefix_.empty())
       resolver_url_prefix_ = GetParam(kContextualSearchResolverUrl);
   }
@@ skipping 26 matching lines @@
                          &is_decode_mentions_disabled_);
 }
 
 bool ContextualSearchFieldTrial::IsContextualCardsBarIntegrationEnabled() {
   return GetBooleanParam(
       switches::kEnableContextualSearchContextualCardsBarIntegration,
       &is_contextual_cards_bar_integration_enabled_cached_,
       &is_contextual_cards_bar_integration_enabled_);
 }
 
+int ContextualSearchFieldTrial::GetContextualCardsVersion() {
+  return GetIntParamValueOrDefault(kContextualCardsVersionParamName, 0,
+                                   &is_contextual_cards_version_cached_,
+                                   &contextual_cards_version_);
+}
+
 bool ContextualSearchFieldTrial::GetBooleanParam(const std::string& name,
                                                  bool* is_value_cached,
                                                  bool* cached_value) {
   if (!*is_value_cached) {
     *is_value_cached = true;
     std::string string_value = GetSwitch(name);
     // A switch with an empty value is true.
     bool has_switch = HasSwitch(name);
     if (has_switch && string_value.empty())
       string_value = kAnyNonEmptyValue;
@@ skipping 32 matching lines @@
   if (!HasSwitch(name))
     return std::string();
   else
     return base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(name);
 }
 
 std::string ContextualSearchFieldTrial::GetParam(const std::string& name) {
   return variations::GetVariationParamValue(kContextualSearchFieldTrialName,
                                             name);
 }