compiler: omit field name for embedded fields in reflection string

This matches the gc compiler.
    
    The test case was sent for the master repo as
    https://golang.org/cl/91138.
    
    Fixes golang/go#23620
    
    Reviewed-on: https://go-review.googlesource.com/91139

From-SVN: r257300

gcc/go/gofrontend/MERGE

@@ -1,4 +1,4 @@
-b833695618d1a5d9d531f5ba0f9c07c7e35e0073
+023c3d4358d101c71ac1436065690eaec2ce138e
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.

gcc/go/gofrontend/types.cc

@@ -6417,11 +6417,11 @@ Struct_type::do_reflection(Gogo* gogo, std::string* ret) const
       if (p != this->fields_->begin())
 	ret->push_back(';');
       ret->push_back(' ');
-      if (p->is_anonymous())
-	ret->push_back('?');
-      else
-	ret->append(Gogo::unpack_hidden_name(p->field_name()));
-      ret->push_back(' ');
+      if (!p->is_anonymous())
+	{
+	  ret->append(Gogo::unpack_hidden_name(p->field_name()));
+	  ret->push_back(' ');
+	}
       if (p->is_anonymous()
 	  && p->type()->named_type() != NULL
 	  && p->type()->named_type()->is_alias())

libgo/go/reflect/all_test.go

@@ -170,6 +170,14 @@ var typeTests = []pair{
 	}{},
 		"interface { reflect_test.a(func(func(int) int) func(func(int)) int); reflect_test.b() }",
 	},
+	{struct {
+		x struct {
+			int32
+			int64
+		}
+	}{},
+		"struct { int32; int64 }",
+	},
 }
 
 var valueTests = []pair{