Convert the C++ Style Guide Away from scoped_comptr.h

scoped_comptr.h is going away.

BUG=638327

Change-Id: Iedfc41cda41e717eda28f593b129207c3749891e
Reviewed-on: https://chromium-review.googlesource.com/724232
Commit-Queue: Robert Liao <robliao@chromium.org>
Reviewed-by: danakj <danakj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#509647}

styleguide/c++/c++.md

@@ -162,7 +162,7 @@ Place platform-specific #includes in their own section below the "normal"
 
   #if defined(OS_WIN)
   #include <windows.h>
-  #include "base/win/scoped_comptr.h"
+  #include "base/win/com_init_util.h"
   #elif defined(OS_POSIX)
   #include "base/posix/global_descriptors.h"
   #endif