Add a buildflag to use the handle verifier in a per module mode.

base/win/scoped_handle.h

Index: base/win/scoped_handle.h
diff --git a/base/win/scoped_handle.h b/base/win/scoped_handle.h
index 6603e681109d6b0d1c342f7e42898d04a4a712fd..782f55dd706bf159942f4e401a584f1e14160949 100644
--- a/base/win/scoped_handle.h
+++ b/base/win/scoped_handle.h
@@ -13,6 +13,7 @@
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/move.h"
+#include "base/win/base_features.h"
 
 // TODO(rvargas): remove this with the rest of the verifier.
 #if defined(COMPILER_MSVC)
@@ -152,6 +153,7 @@ class DummyVerifierTraits {
   DISALLOW_IMPLICIT_CONSTRUCTORS(DummyVerifierTraits);
 };
 
+#if BUILDFLAG(ENABLE_HANDLE_VERIFIER)
 // Performs actual run-time tracking.
 class BASE_EXPORT VerifierTraits {
  public:
@@ -168,6 +170,19 @@ class BASE_EXPORT VerifierTraits {
 
 typedef GenericScopedHandle<HandleTraits, VerifierTraits> ScopedHandle;
 
+// This testing function returns the module that the ActiveVerifier concrete
+// implementation was instantiated in.
+BASE_EXPORT HMODULE GetHandleVerifierModuleForTesting();
+#else
+typedef GenericScopedHandle<HandleTraits, DummyVerifierTraits> ScopedHandle;
+#endif  // BUILDFLAG(ENABLE_HANDLE_VERIFIER)
+
+// This should be called whenever the OS is closing a handle, if extended
+// verification of improper handle closing is desired. If |handle| is being
+// tracked by the handle verifier and ScopedHandle is not the one closing it,
+// a CHECK is generated.
+BASE_EXPORT void OnHandleBeingClosed(HANDLE handle);
+
 // This function may be called by the embedder to disable the use of
 // VerifierTraits at runtime. It has no effect if DummyVerifierTraits is used
 // for ScopedHandle.
@@ -179,10 +194,6 @@ BASE_EXPORT void DisableHandleVerifier();
 // a CHECK is generated.
 BASE_EXPORT void OnHandleBeingClosed(HANDLE handle);
 
-// This testing function returns the module that the ActiveVerifier concrete
-// implementation was instantiated in.
-BASE_EXPORT HMODULE GetHandleVerifierModuleForTesting();
-
 }  // namespace win
 }  // namespace base