Add a probability to Alternate-Protocol support.

net/http/http_server_properties_impl.h

Index: net/http/http_server_properties_impl.h
diff --git a/net/http/http_server_properties_impl.h b/net/http/http_server_properties_impl.h
index c65d5e3cf8e2f6260a875b5295e6de2dc1375bbf..7d7ec11c559ec098087282ae7c676427ab53311a 100644
--- a/net/http/http_server_properties_impl.h
+++ b/net/http/http_server_properties_impl.h
@@ -55,7 +55,7 @@ class NET_EXPORT HttpServerPropertiesImpl
   // Debugging to simulate presence of an AlternateProtocol.
   // If we don't have an alternate protocol in the map for any given host/port
   // pair, force this ProtocolPortPair.
-  static void ForceAlternateProtocol(const PortAlternateProtocolPair& pair);
+  static void ForceAlternateProtocol(const AlternateProtocolInfo& pair);
   static void DisableForcedAlternateProtocol();
 
   // Returns the canonical host suffix for |server|, or std::string() if none
@@ -84,14 +84,15 @@ class NET_EXPORT HttpServerPropertiesImpl
 
   // Returns the Alternate-Protocol and port for |server|.
   // HasAlternateProtocol(server) must be true.
-  virtual PortAlternateProtocolPair GetAlternateProtocol(
+  virtual AlternateProtocolInfo GetAlternateProtocol(
       const HostPortPair& server) OVERRIDE;
 
   // Sets the Alternate-Protocol for |server|.
   virtual void SetAlternateProtocol(
       const HostPortPair& server,
       uint16 alternate_port,
-      AlternateProtocol alternate_protocol) OVERRIDE;
+      AlternateProtocol alternate_protocol,
+      double probability) OVERRIDE;
 
   // Sets the Alternate-Protocol for |server| to be BROKEN.
   virtual void SetBrokenAlternateProtocol(const HostPortPair& server) OVERRIDE;
@@ -112,6 +113,9 @@ class NET_EXPORT HttpServerPropertiesImpl
   virtual void SetAlternateProtocolExperiment(
       AlternateProtocolExperiment experiment) OVERRIDE;
 
+  virtual void SetAlternateProtocolProbabilityThreshold(
+      double threshold) OVERRIDE;
+
   virtual AlternateProtocolExperiment GetAlternateProtocolExperiment()
       const OVERRIDE;
 
@@ -184,6 +188,8 @@ class NET_EXPORT HttpServerPropertiesImpl
   // ".googlevideo.com", ".googleusercontent.com") of canoncial hostnames.
   CanonicalSufficList canoncial_suffixes_;
 
+  double alternate_protocol_probability_threshold_;
+
   base::WeakPtrFactory<HttpServerPropertiesImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(HttpServerPropertiesImpl);