Introduce new SpdyConstants class

net/spdy/spdy_protocol.h

Index: net/spdy/spdy_protocol.h
diff --git a/net/spdy/spdy_protocol.h b/net/spdy/spdy_protocol.h
index fd1351a487e48b3f8eb7f774689881325c7434a5..e871d2c24c8d1a47f20162864ff94be5267212a8 100644
--- a/net/spdy/spdy_protocol.h
+++ b/net/spdy/spdy_protocol.h
@@ -384,6 +384,28 @@ typedef std::map<std::string, std::string> SpdyNameValueBlock;
 
 typedef uint64 SpdyPingId;
 
+// TODO(hkhalil): Add direct testing for this? It won't increase coverage any,
+// but is good to do anyway.
+class SpdyConstants {
+ public:
+  // Returns true if a given on-the-wire enumeration of a frame type is valid
+  // for a given protocol version, false otherwise.
+  static bool IsValidFrameType(SpdyMajorVersion version, int frame_type_field);
+
+  // Parses a frame type from an on-the-wire enumeration of a given protocol
+  // version.
+  // Behavior is undefined for invalid frame type fields; consumers should first
+  // use IsValidFrameType() to verify validity of frame type fields.
+  static SpdyFrameType ParseFrameType(SpdyMajorVersion version,
+                                      int frame_type_field);
+
+  // Serializes a given frame type to the on-the-wire enumeration value for the
+  // given protocol version.
+  // Returns -1 on failure (I.E. Invalid frame type for the given version).
+  static int SerializeFrameType(SpdyMajorVersion version,
+                                SpdyFrameType frame_type);
+};
+
 class SpdyFrame;
 typedef SpdyFrame SpdySerializedFrame;