Mojom Parser: Populate |serialized_runimte_type_info| field during serialization.

mojom/mojom_parser/mojom/user_defined_types.go

Index: mojom/mojom_parser/mojom/user_defined_types.go
diff --git a/mojom/mojom_parser/mojom/user_defined_types.go b/mojom/mojom_parser/mojom/user_defined_types.go
index c0a5c1bf09c62552a09c0953ddc8820c6d1f1cc4..3dd9c5caec73862c537e8331146455457d23dbb4 100644
--- a/mojom/mojom_parser/mojom/user_defined_types.go
+++ b/mojom/mojom_parser/mojom/user_defined_types.go
@@ -9,6 +9,7 @@ import (
 	"fmt"
 	"math"
 	"mojom/mojom_parser/lexer"
+	"sort"
 	"strings"
 )
 
@@ -145,6 +146,7 @@ func (b *UserDefinedTypeBase) FindReachableTypes() []string {
 		}
 		i++
 	}
+	sort.Strings(typeKeys)
 	return typeKeys
 }
 
@@ -152,6 +154,9 @@ func (b *UserDefinedTypeBase) FindReachableTypes() []string {
 // It performs a depth-first search through the type graph while populating
 // |reachableSet| with the UserDefinedTypes encountered during the search.
 func findReachableTypes(udt UserDefinedType, reachableSet UserDefinedTypeSet) {
+	if udt == nil {
+		panic("udt is nil")
+	}
 	if reachableSet.Contains(udt) {
 		return
 	}
@@ -186,7 +191,9 @@ func findReachableTypes(udt UserDefinedType, reachableSet UserDefinedTypeSet) {
 			// There is an edge in the type graph from this interface type to
 			// the type of a request or response parameter.
 			findReachableTypes(object.Parameters, reachableSet)
-			findReachableTypes(object.ResponseParameters, reachableSet)
+			if object.ResponseParameters != nil {
+				findReachableTypes(object.ResponseParameters, reachableSet)
+			}
 		}
 	}
 }