Go bindings: Don't import 'fmt' unless it is needed.

mojo/go/tests/enums_test.go

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package tests
 
 import (
+        test_enums_no_type_info "mojo/go/tests/test_enums"
         "mojo/public/interfaces/bindings/tests/test_enums"
         "testing"
 )
 
+// TestEnums just exercises the generated go code for enums. It tests that
+// the generated enum value constants are of the correct type. The difference
+// between test_enums and test_enums_no_type_info is that the former has been generated
+// using 'generate_type_info = true' and the latter has not. Our only goal
+// in including both is to minimally exercise both generation pathways.
 func TestEnums(t *testing.T) {
         if test_enums.TestEnum_Foo != IdentityEnum1(test_enums.TestEnum_Foo) {
                 t.Errorf("IdentityEnum1 failure.")
         }
 
         if test_enums.TestEnum2_Foo != IdentityEnum2(test_enums.TestEnum2_Foo) {
                 t.Errorf("IdentityEnum1 failure.")
         }
+
+        if test_enums_no_type_info.TestEnum_Foo != IdentityEnumB1(test_enums_no_type_info.TestEnum_Foo) {
+                t.Errorf("IdentityEnum1 failure.")
+        }
+
+        if test_enums_no_type_info.TestEnum2_Foo != IdentityEnumB2(test_enums_no_type_info.TestEnum2_Foo) {
+                t.Errorf("IdentityEnum1 failure.")
+        }
 }
 
 func IdentityEnum1(x test_enums.TestEnum) test_enums.TestEnum {
         return x
 }
 
 func IdentityEnum2(x test_enums.TestEnum2) test_enums.TestEnum2 {
         return x
 }
+
+func IdentityEnumB1(x test_enums_no_type_info.TestEnum) test_enums_no_type_info.TestEnum {
+        return x
+}
+
+func IdentityEnumB2(x test_enums_no_type_info.TestEnum2) test_enums_no_type_info.TestEnum2 {
+        return x
+}