Revert 253993 "Default to VS2013 on Windows"

trunk/src/build/gyp_chromium

Index: trunk/src/build/gyp_chromium
===================================================================
--- trunk/src/build/gyp_chromium	(revision 254037)
+++ trunk/src/build/gyp_chromium	(working copy)
@@ -471,8 +471,9 @@
   # If on Windows, request that depot_tools install/update the automatic
   # toolchain, and then use it (unless opted-out).
   vs2013_runtime_dll_dirs = None
+  # TODO(scottmg): Temporarily default to off, see http://crbug.com/345993.
   depot_tools_win_toolchain = \
-      bool(int(os.environ.get('DEPOT_TOOLS_WIN_TOOLCHAIN', '1')))
+      bool(int(os.environ.get('DEPOT_TOOLS_WIN_TOOLCHAIN', '0')))
   if sys.platform in ('win32', 'cygwin') and depot_tools_win_toolchain:
     import find_depot_tools
     depot_tools_path = find_depot_tools.add_depot_tools_to_path()