proto, internal/proto: fix tests broken by latest v2 module

Correct a failure in (un)marshaling extensions caused by expecting a
*[]T where we now use a []T.

Include unknown fields in text marshal output.

Change-Id: Ica1ecab1f0768a1208b00915884ccd8026cc53a8
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/204803
Reviewed-by: Joe Tsai <[email protected]>

Author: neild

internal/proto/text.go

@@ -51,6 +51,7 @@ func (tm *TextMarshaler) Marshal(w io.Writer, pb Message) error {
 	}
 	mo := prototext.MarshalOptions{
 		AllowPartial: true,
+		EmitUnknown:  true,
 		Indent:       ind,
 	}
 	if !tm.ExpandAny {

proto/table_marshal.go

@@ -393,18 +393,12 @@ func (u *marshalInfo) getExtElemInfo(desc *ExtensionDesc) *marshalElemInfo {
 		t = t.Elem()
 	}
 	sizer, marshaler := typeMarshaler(t, tags, false, false)
-	var deref bool
-	if t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8 {
-		t = reflect.PtrTo(t)
-		deref = true
-	}
 	e = &marshalElemInfo{
 		wiretag:   uint64(tag)<<3 | wt,
 		tagsize:   SizeVarint(uint64(tag) << 3),
 		sizer:     sizer,
 		marshaler: marshaler,
 		isptr:     t.Kind() == reflect.Ptr,
-		deref:     deref,
 	}
 
 	// update cache