Move EnableSpdy from HttpNetworkLayer to IOThread.

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 af95a721793ddbd92324d5dbab55b0b665f43a72..c7bf1ec7799dfc748f6530d79c85347c353755a5 100644
--- a/chrome/browser/io_thread.h
+++ b/chrome/browser/io_thread.h
@@ -170,6 +170,16 @@ class IOThread : public content::BrowserThreadDelegate {
 
   void InitializeNetworkOptions(const CommandLine& parsed_command_line);
 
+  // Enable the spdy protocol.
+  // Without calling this function, SPDY is disabled.  The mode can be:

[Ryan Sleevi, 2012/11/27 20:06:38]

This is... an odd default.

Why is SPDY disabled by default?

[Ryan Hamilton, 2012/11/27 20:52:53]

That comment appears to be incorrect.  I've revamped it.

+  //   ""            : (default) SSL and compression are enabled, flow
+  //                   control disabled.
+  //   "no-ssl"      : disables SSL.
+  //   "no-compress" : disables compression.
+  //   "flow-control": enables flow control.
+  //   "none"        : disables both SSL and compression.
+  void EnableSpdy(const std::string& mode);
+
   // Global state must be initialized on the IO thread, then this
   // method must be invoked on the UI thread.
   void InitSystemRequestContext();