HTTP2 draft 13: support unknown frame types and settings types as extensions.

net/spdy/spdy_protocol.cc

Index: net/spdy/spdy_protocol.cc
diff --git a/net/spdy/spdy_protocol.cc b/net/spdy/spdy_protocol.cc
index 6b55b11ea945e09e34029e8c4d30dc430041d03a..1ab0d5bdcf40ba7af0e1ac81c54432daedb4e722 100644
--- a/net/spdy/spdy_protocol.cc
+++ b/net/spdy/spdy_protocol.cc
@@ -43,13 +43,19 @@ bool SpdyConstants::IsValidFrameType(SpdyMajorVersion version,
       return true;
     case SPDY4:
     case SPDY5:
+      // Check for recognized extensions.
+      if (frame_type_field == SerializeFrameType(version, ALTSVC) ||
+          frame_type_field == SerializeFrameType(version, BLOCKED)) {
+        return true;
+      }
+
       // DATA is the first valid frame.
       if (frame_type_field < SerializeFrameType(version, DATA)) {
         return false;
       }
 
-      // BLOCKED is the last valid frame.
-      if (frame_type_field > SerializeFrameType(version, BLOCKED)) {
+      // CONTINUATION is the last valid frame.
+      if (frame_type_field > SerializeFrameType(version, CONTINUATION)) {
         return false;
       }
 
@@ -168,6 +174,7 @@ int SpdyConstants::SerializeFrameType(SpdyMajorVersion version,
           return 8;
         case CONTINUATION:
           return 9;
+        // ALTSVC and BLOCKED are extensions.
         case ALTSVC:
           return 10;
         case BLOCKED: