Win-clang update script: make an auxiliary copy of the sanitizer headers

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index d8e60f182335a6007d2cea3c3ecede989ec27f01..b77bc82b0915451be79fff964aa8509e4a301f3c 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -5060,6 +5060,9 @@
                 'AdditionalOptions': [
                   '-fsanitize=address',
                 ],
+                'AdditionalIncludeDirectories': [

[Reid Kleckner, 2014/05/15 23:58:52]

Can you comment that MSVC needs to be able to include some internal sanitizer
headers, so we have to add this include path?

[hans, 2014/05/16 00:20:57]

Done.

+                  '<(DEPTH)/<(make_clang_dir)/lib/clang/3.5.0/include_sanitizer',

[Reid Kleckner, 2014/05/15 23:58:52]

80cols

[hans, 2014/05/16 00:20:57]

We don't seem to use the 80-cols limit for lines like this in this file.

+                ],
               },
               'VCLinkerTool': {
                 'AdditionalLibraryDirectories': [