Update DEPS to bring in latest Chrome win reference build.

DEPS

 vars = {
   # Use this googlecode_url variable only if there is an internal mirror for it.
   # If you do not know, use the full path while defining your new deps entry.
   "googlecode_url": "http://%s.googlecode.com/svn",
   "webkit_trunk": "http://svn.webkit.org/repository/webkit/trunk",
   "nacl_trunk": "http://src.chromium.org/native_client/trunk",
   "webkit_revision": "73514",
   "skia_revision": "632",
   "chromium_git": "http://git.chromium.org/git",
   "swig_revision": "40423",
@@ skipping 171 matching lines @@
     "/trunk/deps/third_party/libsrtp@60080",
 
   "src/third_party/yasm/source/patched-yasm":
     "/trunk/deps/third_party/yasm/patched-yasm@50870",
 }
 
 
 deps_os = {
   "win": {
     "src/chrome/tools/test/reference_build/chrome":
-      "/trunk/deps/reference_builds/chrome@41984",
+      "/trunk/deps/reference_builds/chrome@68691",
 
     "src/third_party/cygwin":
       "/trunk/deps/third_party/cygwin@66844",
 
     "src/third_party/python_26":
       "/trunk/tools/third_party/python_26@67105",
 
     "src/third_party/lighttpd":
       "/trunk/deps/third_party/lighttpd@33727",
 
     "src/third_party/ffmpeg/binaries/chromium/win/ia32":
       "/trunk/deps/third_party/ffmpeg/binaries/win@" + Var("ffmpeg_revision"),
 
     # Chrome Frame related deps
     "src/third_party/xulrunner-sdk":
       "/trunk/deps/third_party/xulrunner-sdk@17887",
     "src/chrome_frame/tools/test/reference_build/chrome":
-      "/trunk/deps/reference_builds/chrome@51194",
+      "/trunk/deps/reference_builds/chrome@68691",
 
     # Parses Windows PE/COFF executable format.
     "src/third_party/pefile":
       (Var("googlecode_url") % "pefile") + "/trunk@63",
 
     # NSS, for SSLClientSocketNSS.
     "src/third_party/nss":
       "/trunk/deps/third_party/nss@61580",
 
     "src/third_party/swig/win":
@@ skipping 80 matching lines @@
 ]
 
 
 hooks = [
   {
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     "pattern": ".",
     "action": ["python", "src/build/gyp_chromium"],
   },
 ]