Remove requirement that mojo::Environment be instantiated.

mojo/public/cpp/environment/lib/environment.cc

Index: mojo/public/cpp/environment/lib/environment.cc
diff --git a/mojo/public/cpp/environment/lib/environment.cc b/mojo/public/cpp/environment/lib/environment.cc
index 822497030bc6fa64166b65761ef89a3f883a3167..73f866811bcfd8984a6b8272852b42734a324969 100644
--- a/mojo/public/cpp/environment/lib/environment.cc
+++ b/mojo/public/cpp/environment/lib/environment.cc
@@ -13,53 +13,27 @@
 
 namespace mojo {
 
-namespace {
-
-const MojoAsyncWaiter* g_default_async_waiter = nullptr;
-const MojoLogger* g_default_logger = nullptr;
-
-void Init(const MojoAsyncWaiter* default_async_waiter,
-          const MojoLogger* default_logger) {
-  g_default_async_waiter = default_async_waiter
-                               ? default_async_waiter
-                               : &internal::kDefaultAsyncWaiter;
-  g_default_logger =
-      default_logger ? default_logger : &internal::kDefaultLogger;
-}
-
-}  // namespace
-
-Environment::Environment() {
-  Init(nullptr, nullptr);
-}
-
-Environment::Environment(const MojoAsyncWaiter* default_async_waiter,
-                         const MojoLogger* default_logger) {
-  Init(default_async_waiter, default_logger);
-}
-
-Environment::~Environment() {
-  // TODO(vtl): Maybe we should allow nesting, and restore previous default
-  // async waiters and loggers?
-  g_default_async_waiter = nullptr;
-  g_default_logger = nullptr;
-}
+const MojoAsyncWaiter* g_default_async_waiter = &internal::kDefaultAsyncWaiter;
+const MojoLogger* g_default_logger = &internal::kDefaultLogger;
 
 // static
 const MojoAsyncWaiter* Environment::GetDefaultAsyncWaiter() {
-  assert(g_default_async_waiter);  // Fails if not "inside" |Environment|.
   return g_default_async_waiter;
 }
 
 // static
+void Environment::SetDefaultAsyncWaiter(const MojoAsyncWaiter* async_waiter) {
+  g_default_async_waiter =
+      async_waiter ? async_waiter : &internal::kDefaultAsyncWaiter;
+}
+
+// static
 const MojoLogger* Environment::GetDefaultLogger() {
-  assert(g_default_logger);  // Fails if not "inside" |Environment|.
   return g_default_logger;
 }
 
 // static
 void Environment::SetDefaultLogger(const MojoLogger* logger) {
-  assert(g_default_logger);  // Fails if not "inside" |Environment|.
   g_default_logger = logger ? logger : &internal::kDefaultLogger;
 }