aura: Require explicit ownership of the Env instance.

ash/test/test_suite.cc

Index: ash/test/test_suite.cc
diff --git a/ash/test/test_suite.cc b/ash/test/test_suite.cc
index c39c76bdbef4ad251c415bb2d1585bd2a1030ac6..fd6b67cddb6e7d2b49226ff5cf7dac12796c286f 100644
--- a/ash/test/test_suite.cc
+++ b/ash/test/test_suite.cc
@@ -59,11 +59,11 @@ void AuraShellTestSuite::Initialize() {
       "en-US", NULL, ui::ResourceBundle::LOAD_COMMON_RESOURCES);
 
   base::DiscardableMemoryAllocator::SetInstance(&discardable_memory_allocator_);
-  aura::Env::CreateInstance(true);
+  env_ = aura::Env::CreateInstance();
 }
 
 void AuraShellTestSuite::Shutdown() {
-  aura::Env::DeleteInstance();
+  env_.reset();
   ui::ResourceBundle::CleanupSharedInstance();
 #if defined(OS_WIN)
   com_initializer_.reset();