Refactor GOAWAY status code handling, also handle SPDY4/HTTP2 status codes.

net/spdy/spdy_framer.cc

Index: net/spdy/spdy_framer.cc
diff --git a/net/spdy/spdy_framer.cc b/net/spdy/spdy_framer.cc
index 5242e806b36b2d77aaba722e8dfb61c37a362cd1..69d13aabd64950e61a5b2bbcdda6aafe44f55099 100644
--- a/net/spdy/spdy_framer.cc
+++ b/net/spdy/spdy_framer.cc
@@ -1754,10 +1754,10 @@ size_t SpdyFramer::ProcessGoAwayFramePayload(const char* data, size_t len) {
         uint32 status_raw = GOAWAY_OK;
         successful_read = reader.ReadUInt32(&status_raw);
         DCHECK(successful_read);
-        // We've read an unsigned integer, so it's enough to only check
-        // upper bound to ensure the value is in valid range.
-        if (status_raw < GOAWAY_NUM_STATUS_CODES) {
-          status = static_cast<SpdyGoAwayStatus>(status_raw);
+        if (SpdyConstants::IsValidGoAwayStatus(protocol_version(),
+                                               status_raw)) {
+          status = SpdyConstants::ParseGoAwayStatus(protocol_version(),
+                                                    status_raw);
         } else {
           // TODO(hkhalil): Probably best to OnError here, depending on
           // our interpretation of the spec. Keeping with existing liberal