Revert of Remove support for Alt-Svc/Alternate Protocol Probability

chrome/common/chrome_switches.cc

 // 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.
 
 #include "chrome/common/chrome_switches.h"
 
 #include "base/base_switches.h"
 #include "base/command_line.h"
 #include "build/build_config.h"
 
@@ skipping 48 matching lines @@
     "disallow-unchecked-dangerous-downloads";
 #endif
 
 // Don't block outdated plugins.
 const char kAllowOutdatedPlugins[]          = "allow-outdated-plugins";
 
 // By default, an https page cannot run JavaScript, CSS or plugins from http
 // URLs. This provides an override to get the old insecure behavior.
 const char kAllowRunningInsecureContent[]   = "allow-running-insecure-content";
 
+// Specifies the probability threshold for alternative services: an advertised
+// alternative service will only be honored if the advertised probability is
+// greater than or equal to this threshold.
+const char kAlternativeServiceProbabilityThreshold[] =
+    "alternative-service-probability-threshold";
+
 // Prevents Chrome from requiring authorization to run certain widely installed
 // but less commonly used plugins.
 const char kAlwaysAuthorizePlugins[]        = "always-authorize-plugins";
 
 // Specifies that the extension-app with the specified id should be launched
 // according to its configuration.
 const char kAppId[]                         = "app-id";
 
 // Specifies that the associated value should be launched in "application"
 // mode.
@@ skipping 1301 matching lines @@
 
 // -----------------------------------------------------------------------------
 // DO NOT ADD YOUR CRAP TO THE BOTTOM OF THIS FILE.
 //
 // You were going to just dump your switches here, weren't you? Instead, please
 // put them in alphabetical order above, or in order inside the appropriate
 // ifdef at the bottom. The order should match the header.
 // -----------------------------------------------------------------------------
 
 }  // namespace switches