[PATCH] clang-cl: Support /showIncludes

[Reid Kleckner]

  LGTM


================
Comment at: lib/Driver/Tools.cpp:3728
@@ +3727,3 @@
+
+  if (Args.hasArg(options::OPT__SLASH_showIncludes))
+    CmdArgs.push_back("--show-includes");
----------------
Can this be an alias?


http://llvm-reviews.chandlerc.com/D1333