This change enables FieldTrial for SPDY. When --use-spdy=npn is used, field test won't be enabled.

However, when that flag is missing, A/B test is added to browser_main.cc. Trial A: use npn and spdy. B: use npn but no spdy. C: do nothing. A and B are set to zero for now
The histograms we collect are: 
1. Page begin to finish time when spdy is enabled/disabled across all sites;
2. Page begin to finish time when spdy is used on sites that support spdy and when spdy is intentionally ignored. 


BUG=43997
TEST=Don't use --use-spdy=npn, manually change _npn_nospdy and _npn_withspdy percentile and go to spdy supported sites.

Review URL: http://codereview.chromium.org/2036012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@47896 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 14 insertions, 0 deletions

diff --git a/net/socket/ssl_client_socket.h b/net/socket/ssl_client_socket.h
index 77537ea..961447b 100644
--- a/net/socket/ssl_client_socket.h
+++ b/net/socket/ssl_client_socket.h
@@ -22,6 +22,8 @@ class SSLInfo;
 //
 class SSLClientSocket : public ClientSocket {
  public:
+  SSLClientSocket() : was_npn_negotiated_(false) {
+  }
   // Next Protocol Negotiation (NPN) allows a TLS client and server to come to
   // an agreement about the application level protocol to speak over a
   // connection.
@@ -68,6 +70,18 @@ class SSLClientSocket : public ClientSocket {
       return kProtoUnknown;
     }
   }
+
+  virtual bool wasNpnNegotiated() const {
+    return was_npn_negotiated_;
+  }
+
+  virtual bool setWasNpnNegotiated(bool negotiated) {
+    return was_npn_negotiated_ = negotiated;
+  }
+
+ private:
+  // True if NPN was responded to, independent of selecting SPDY or HTTP.
+  bool was_npn_negotiated_;
 };
 
 }  // namespace net