cmd/protoc-gen-go: change some arrays to slices to save bytes

Using arrays in the generated reflection information adds unnecessary
eq and hash functions being added to the package. Change to slices
to reduce bloat.

Change-Id: I1a4f6d59021644d93dd6c24679b9233141e89a75
Reviewed-on: https://go-review.googlesource.com/c/164640
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
diff --git a/internal/testprotos/test/test.pb.go b/internal/testprotos/test/test.pb.go
index 3e62616..8ac0de0 100644
--- a/internal/testprotos/test/test.pb.go
+++ b/internal/testprotos/test/test.pb.go
@@ -2740,8 +2740,8 @@
 
 var File_test_test_proto protoreflect.FileDescriptor
 
-var xxx_File_test_test_proto_enumTypes [4]protoreflect.EnumType
-var xxx_File_test_test_proto_messageTypes [30]protoimpl.MessageType
+var xxx_File_test_test_proto_enumTypes = make([]protoreflect.EnumType, 4)
+var xxx_File_test_test_proto_messageTypes = make([]protoimpl.MessageType, 30)
 var xxx_File_test_test_proto_goTypes = []interface{}{
 	(ForeignEnum)(0),                          // 0: goproto.proto.test.ForeignEnum
 	(TestReservedEnumFields)(0),               // 1: goproto.proto.test.TestReservedEnumFields
@@ -2871,18 +2871,18 @@
 }
 
 func init() {
-	var messageTypes [30]protoreflect.MessageType
-	var extensionTypes [37]protoreflect.ExtensionType
+	messageTypes := make([]protoreflect.MessageType, 30)
+	extensionTypes := make([]protoreflect.ExtensionType, 37)
 	File_test_test_proto = protoimpl.FileBuilder{
 		RawDescriptor:        xxx_File_test_test_proto_rawdesc,
 		GoTypes:              xxx_File_test_test_proto_goTypes,
 		DependencyIndexes:    xxx_File_test_test_proto_depIdxs,
-		EnumOutputTypes:      xxx_File_test_test_proto_enumTypes[:],
-		MessageOutputTypes:   messageTypes[:],
-		ExtensionOutputTypes: extensionTypes[:],
+		EnumOutputTypes:      xxx_File_test_test_proto_enumTypes,
+		MessageOutputTypes:   messageTypes,
+		ExtensionOutputTypes: extensionTypes,
 	}.Init()
 	messageGoTypes := xxx_File_test_test_proto_goTypes[4:][:30]
-	for i, mt := range messageTypes[:] {
+	for i, mt := range messageTypes {
 		xxx_File_test_test_proto_messageTypes[i].GoType = reflect.TypeOf(messageGoTypes[i])
 		xxx_File_test_test_proto_messageTypes[i].PBType = mt
 	}
diff --git a/internal/testprotos/test/test_import.pb.go b/internal/testprotos/test/test_import.pb.go
index a531004..c02f84c 100644
--- a/internal/testprotos/test/test_import.pb.go
+++ b/internal/testprotos/test/test_import.pb.go
@@ -121,8 +121,8 @@
 
 var File_test_test_import_proto protoreflect.FileDescriptor
 
-var xxx_File_test_test_import_proto_enumTypes [1]protoreflect.EnumType
-var xxx_File_test_test_import_proto_messageTypes [1]protoimpl.MessageType
+var xxx_File_test_test_import_proto_enumTypes = make([]protoreflect.EnumType, 1)
+var xxx_File_test_test_import_proto_messageTypes = make([]protoimpl.MessageType, 1)
 var xxx_File_test_test_import_proto_goTypes = []interface{}{
 	(ImportEnum)(0),       // 0: goproto.proto.test.ImportEnum
 	(*ImportMessage)(nil), // 1: goproto.proto.test.ImportMessage
@@ -130,16 +130,16 @@
 var xxx_File_test_test_import_proto_depIdxs = []int32{}
 
 func init() {
-	var messageTypes [1]protoreflect.MessageType
+	messageTypes := make([]protoreflect.MessageType, 1)
 	File_test_test_import_proto = protoimpl.FileBuilder{
 		RawDescriptor:      xxx_File_test_test_import_proto_rawdesc,
 		GoTypes:            xxx_File_test_test_import_proto_goTypes,
 		DependencyIndexes:  xxx_File_test_test_import_proto_depIdxs,
-		EnumOutputTypes:    xxx_File_test_test_import_proto_enumTypes[:],
-		MessageOutputTypes: messageTypes[:],
+		EnumOutputTypes:    xxx_File_test_test_import_proto_enumTypes,
+		MessageOutputTypes: messageTypes,
 	}.Init()
 	messageGoTypes := xxx_File_test_test_import_proto_goTypes[1:][:1]
-	for i, mt := range messageTypes[:] {
+	for i, mt := range messageTypes {
 		xxx_File_test_test_import_proto_messageTypes[i].GoType = reflect.TypeOf(messageGoTypes[i])
 		xxx_File_test_test_import_proto_messageTypes[i].PBType = mt
 	}
diff --git a/internal/testprotos/test/test_public.pb.go b/internal/testprotos/test/test_public.pb.go
index 7144ae8..5533185 100644
--- a/internal/testprotos/test/test_public.pb.go
+++ b/internal/testprotos/test/test_public.pb.go
@@ -74,22 +74,22 @@
 
 var File_test_test_public_proto protoreflect.FileDescriptor
 
-var xxx_File_test_test_public_proto_messageTypes [1]protoimpl.MessageType
+var xxx_File_test_test_public_proto_messageTypes = make([]protoimpl.MessageType, 1)
 var xxx_File_test_test_public_proto_goTypes = []interface{}{
 	(*PublicImportMessage)(nil), // 0: goproto.proto.test.PublicImportMessage
 }
 var xxx_File_test_test_public_proto_depIdxs = []int32{}
 
 func init() {
-	var messageTypes [1]protoreflect.MessageType
+	messageTypes := make([]protoreflect.MessageType, 1)
 	File_test_test_public_proto = protoimpl.FileBuilder{
 		RawDescriptor:      xxx_File_test_test_public_proto_rawdesc,
 		GoTypes:            xxx_File_test_test_public_proto_goTypes,
 		DependencyIndexes:  xxx_File_test_test_public_proto_depIdxs,
-		MessageOutputTypes: messageTypes[:],
+		MessageOutputTypes: messageTypes,
 	}.Init()
 	messageGoTypes := xxx_File_test_test_public_proto_goTypes[0:][:1]
-	for i, mt := range messageTypes[:] {
+	for i, mt := range messageTypes {
 		xxx_File_test_test_public_proto_messageTypes[i].GoType = reflect.TypeOf(messageGoTypes[i])
 		xxx_File_test_test_public_proto_messageTypes[i].PBType = mt
 	}
diff --git a/internal/testprotos/test/test_weak.pb.go b/internal/testprotos/test/test_weak.pb.go
index e42f7ff..97698a7 100644
--- a/internal/testprotos/test/test_weak.pb.go
+++ b/internal/testprotos/test/test_weak.pb.go
@@ -74,22 +74,22 @@
 
 var File_test_test_weak_proto protoreflect.FileDescriptor
 
-var xxx_File_test_test_weak_proto_messageTypes [1]protoimpl.MessageType
+var xxx_File_test_test_weak_proto_messageTypes = make([]protoimpl.MessageType, 1)
 var xxx_File_test_test_weak_proto_goTypes = []interface{}{
 	(*WeakImportMessage)(nil), // 0: goproto.proto.test.WeakImportMessage
 }
 var xxx_File_test_test_weak_proto_depIdxs = []int32{}
 
 func init() {
-	var messageTypes [1]protoreflect.MessageType
+	messageTypes := make([]protoreflect.MessageType, 1)
 	File_test_test_weak_proto = protoimpl.FileBuilder{
 		RawDescriptor:      xxx_File_test_test_weak_proto_rawdesc,
 		GoTypes:            xxx_File_test_test_weak_proto_goTypes,
 		DependencyIndexes:  xxx_File_test_test_weak_proto_depIdxs,
-		MessageOutputTypes: messageTypes[:],
+		MessageOutputTypes: messageTypes,
 	}.Init()
 	messageGoTypes := xxx_File_test_test_weak_proto_goTypes[0:][:1]
-	for i, mt := range messageTypes[:] {
+	for i, mt := range messageTypes {
 		xxx_File_test_test_weak_proto_messageTypes[i].GoType = reflect.TypeOf(messageGoTypes[i])
 		xxx_File_test_test_weak_proto_messageTypes[i].PBType = mt
 	}