Add field-initializing factory static methods to generated mojo unions.

mojo/public/interfaces/bindings/tests/test_unions.mojom

Index: mojo/public/interfaces/bindings/tests/test_unions.mojom
diff --git a/mojo/public/interfaces/bindings/tests/test_unions.mojom b/mojo/public/interfaces/bindings/tests/test_unions.mojom
index 41e1ed6ace0fccc12dc8239cef99f9fec5d910c1..b320e2b6b3e623f1b8073790e0cc907da1c82741 100644
--- a/mojo/public/interfaces/bindings/tests/test_unions.mojom
+++ b/mojo/public/interfaces/bindings/tests/test_unions.mojom
@@ -30,6 +30,35 @@ union PodUnion {
   AnExtensibleEnum f_extensible_enum;
 };
 
+union PodUnionWithDuplicates {
+  int8   f_int8;
+  int8   f_int8_other;
+  uint8  f_uint8;
+  uint8  f_uint8_other;
+  int16  f_int16;
+  int16  f_int16_other;
+  uint16 f_uint16;
+  uint16 f_uint16_other;
+  int32  f_int32;
+  int32  f_int32_other;
+  uint32 f_uint32;
+  uint32 f_uint32_other;
+  int64  f_int64;
+  int64  f_int64_other;
+  uint64 f_uint64;
+  uint64 f_uint64_other;
+  float  f_float;
+  float  f_float_other;
+  double f_double;
+  double f_double_other;
+  bool   f_bool;
+  bool   f_bool_other;
+  AnEnum f_enum;
+  AnEnum f_enum_other;
+  AnExtensibleEnum f_extensible_enum;
+  AnExtensibleEnum f_extensible_enum_other;
+};
+
 union ObjectUnion {
   int8   f_int8;
   string f_string;
@@ -42,6 +71,24 @@ union ObjectUnion {
   array<SmallStruct> f_small_structs;
 };
 
+union ObjectUnionWithDuplicates {
+  string f_string;
+  string f_string_other;
+  DummyStruct f_dummy;
+  DummyStruct f_dummy_other;
+  DummyStruct? f_nullable;
+  DummyStruct? f_nullable_other;
+  array<int8> f_array_int8;
+  array<int8> f_array_int8_other;
+  map<string, int8> f_map_int8;
+  map<string, int8> f_map_int8_other;
+  PodUnion f_pod_union;
+  PodUnion f_pod_union_other;
+  // Test that Clone() is defined after SmallStruct is declared.
+  array<SmallStruct> f_small_structs;
+  array<SmallStruct> f_small_structs_other;
+};
+
 union HandleUnion {
   handle f_handle;
   handle<message_pipe> f_message_pipe;
@@ -52,6 +99,23 @@ union HandleUnion {
   SmallCache& f_small_cache_request;
 };
 
+union HandleUnionWithDuplicates {
+  handle f_handle;
+  handle f_handle_other;
+  handle<message_pipe> f_message_pipe;
+  handle<message_pipe> f_message_pipe_other;
+  handle<data_pipe_consumer> f_data_pipe_consumer;
+  handle<data_pipe_consumer> f_data_pipe_consumer_other;
+  handle<data_pipe_producer> f_data_pipe_producer;
+  handle<data_pipe_producer> f_data_pipe_producer_other;
+  handle<shared_buffer> f_shared_buffer;
+  handle<shared_buffer> f_shared_buffer_other;
+  SmallCache f_small_cache;
+  SmallCache f_small_cache_other;
+  SmallCache& f_small_cache_request;
+  SmallCache& f_small_cache_request_other;
+};
+
 struct WrapperStruct {
   ObjectUnion? object_union;
   PodUnion? pod_union;