[SPDY] Add flag to turn on SPDY/3.1 (with per-session flow control)

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index b85012ef98f124a7ee3cd7a6b644d46d527abafe..505d1a7198194299f26309916de0dcf4e3dce82c 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -622,6 +622,9 @@ const char kEnableSdch[]                    = "enable-sdch";
 // Enable SPDY/3. This is a temporary testing flag.
 const char kEnableSpdy3[]                   = "enable-spdy3";
 
+// Enable SPDY/3.1. This is a temporary testing flag.
+const char kEnableSpdy31[]                  = "enable-spdy31";
+
 // Enable SPDY CREDENTIAL frame support.  This is a temporary testing flag.
 const char kEnableSpdyCredentialFrames[]    = "enable-spdy-credential-frames";