Removed need to use "backtrack" in grammar.
diff --git a/com.google.eclipse.protobuf/descriptor.proto b/com.google.eclipse.protobuf/descriptor.proto
index 4eeb43b..d959ce1 100644
--- a/com.google.eclipse.protobuf/descriptor.proto
+++ b/com.google.eclipse.protobuf/descriptor.proto
@@ -35,7 +35,7 @@
// The messages in this file describe the definitions found in .proto files.
// A valid .proto file can be translated directly to a FileDescriptorProto
// without any other information (e.g. without reading its imports).
-
+syntax = "proto2";
package google.protobuf;