Remove requirement that mojo::Environment be instantiated.

mojo/public/cpp/bindings/tests/binding_unittest.cc

Index: mojo/public/cpp/bindings/tests/binding_unittest.cc
diff --git a/mojo/public/cpp/bindings/tests/binding_unittest.cc b/mojo/public/cpp/bindings/tests/binding_unittest.cc
index 752490078371ee34d816fa1edc33286696c08c47..f47e70a296190166909bd674f11c9566b2a42fc3 100644
--- a/mojo/public/cpp/bindings/tests/binding_unittest.cc
+++ b/mojo/public/cpp/bindings/tests/binding_unittest.cc
@@ -7,7 +7,6 @@
 
 #include "mojo/public/cpp/bindings/binding.h"
 #include "mojo/public/cpp/bindings/strong_binding.h"
-#include "mojo/public/cpp/environment/environment.h"
 #include "mojo/public/cpp/system/macros.h"
 #include "mojo/public/cpp/utility/run_loop.h"
 #include "mojo/public/interfaces/bindings/tests/sample_interfaces.mojom.h"
@@ -25,7 +24,6 @@ class BindingTestBase : public testing::Test {
   RunLoop& loop() { return loop_; }
 
  private:
-  Environment env_;
   RunLoop loop_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(BindingTestBase);