Switch some Singletons to use LeakySingleton.

base/debug_util_win.cc

Index: base/debug_util_win.cc
diff --git a/base/debug_util_win.cc b/base/debug_util_win.cc
index b60ba314bcfee3d9326c05ed72d1e92df103da1f..5ddaafd1fa7e1537c74e5eb23bb503f75558dcdf 100644
--- a/base/debug_util_win.cc
+++ b/base/debug_util_win.cc
@@ -86,10 +86,7 @@ bool StringReplace(const wchar_t* input, int value, wchar_t* output,
 class SymbolContext {
  public:
   static SymbolContext* Get() {
-    // We use a leaky singleton because code may call this during process
-    // termination.
-    return
-      Singleton<SymbolContext, LeakySingletonTraits<SymbolContext> >::get();
+    return LeakySingleton<SymbolContext>::get();
   }
 
   // Returns the error code of a failed initialization.