Rename methods and members and const variables to alternative service.

chrome/browser/io_thread.h

Index: chrome/browser/io_thread.h
diff --git a/chrome/browser/io_thread.h b/chrome/browser/io_thread.h
index 93cfa48ea1145ef58121313ec0fa8a637dfea773..4b604560fee864352f57220fef4f851fc61842b2 100644
--- a/chrome/browser/io_thread.h
+++ b/chrome/browser/io_thread.h
@@ -175,7 +175,7 @@ class IOThread : public content::BrowserThreadDelegate {
     Optional<std::string> trusted_spdy_proxy;
     std::set<net::HostPortPair> forced_spdy_exclusions;
     Optional<bool> use_alternate_protocols;
-    Optional<double> alternate_protocol_probability_threshold;
+    Optional<double> alternative_service_probability_threshold;
 
     Optional<bool> enable_quic;
     Optional<bool> enable_quic_for_proxies;
@@ -411,9 +411,9 @@ class IOThread : public content::BrowserThreadDelegate {
       const base::CommandLine& command_line,
       const VariationParameters& quic_trial_params);
 
-  // Returns the alternate protocol probability threshold specified by
+  // Returns the alternative service probability threshold specified by
   // any flags in |command_line| or |quic_trial_params|.
-  static double GetAlternateProtocolProbabilityThreshold(
+  static double GetAlternativeProtocolProbabilityThreshold(
       const base::CommandLine& command_line,
       const VariationParameters& quic_trial_params);