Revert of Change mojo_public_bindings_unittests to use chromium environment.

third_party/mojo/src/mojo/public/cpp/bindings/tests/struct_unittest.cc

Index: third_party/mojo/src/mojo/public/cpp/bindings/tests/struct_unittest.cc
diff --git a/third_party/mojo/src/mojo/public/cpp/bindings/tests/struct_unittest.cc b/third_party/mojo/src/mojo/public/cpp/bindings/tests/struct_unittest.cc
index 24173e58e54a5f1b0cfd9dc0bb1d2e009aa21c96..71069d277655dd25e027173dcd4ce3fb90c3ab89 100644
--- a/third_party/mojo/src/mojo/public/cpp/bindings/tests/struct_unittest.cc
+++ b/third_party/mojo/src/mojo/public/cpp/bindings/tests/struct_unittest.cc
@@ -5,6 +5,7 @@
 #include <string.h>
 
 #include "mojo/public/cpp/bindings/lib/fixed_buffer.h"
+#include "mojo/public/cpp/environment/environment.h"
 #include "mojo/public/cpp/system/message_pipe.h"
 #include "mojo/public/interfaces/bindings/tests/test_structs.mojom.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -71,7 +72,13 @@
   return output.Pass();
 }
 
-using StructTest = testing::Test;
+class StructTest : public testing::Test {
+ public:
+  ~StructTest() override {}
+
+ private:
+  Environment env_;
+};
 
 }  // namespace