Refactor RST_STREAM status code handling.

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 23080accd994ad2c6982d3e639fdaab2a1c28981..5242e806b36b2d77aaba722e8dfb61c37a362cd1 100644
--- a/net/spdy/spdy_framer.cc
+++ b/net/spdy/spdy_framer.cc
@@ -438,6 +438,10 @@ const char* SpdyFramer::StatusCodeToString(int status_code) {
       return "INVALID_CREDENTIALS";
     case RST_STREAM_FRAME_TOO_LARGE:
       return "FRAME_TOO_LARGE";
+    case RST_STREAM_CONNECT_ERROR:
+      return "CONNECT_ERROR";
+    case RST_STREAM_ENHANCE_YOUR_CALM:
+      return "ENHANCE_YOUR_CALM";
   }
   return "UNKNOWN_STATUS";
 }
@@ -1816,10 +1820,8 @@ size_t SpdyFramer::ProcessRstStreamFramePayload(const char* data, size_t len) {
       uint32 status_raw = status;
       bool 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 > RST_STREAM_INVALID &&
-          status_raw < RST_STREAM_NUM_STATUS_CODES) {
+      if (SpdyConstants::IsValidRstStreamStatus(protocol_version(),
+                                                status_raw)) {
         status = static_cast<SpdyRstStreamStatus>(status_raw);
       } else {
         // TODO(hkhalil): Probably best to OnError here, depending on