Update gold linker to 2.23.1

DEPS

 # When adding a new dependency, please update the top-level .gitignore file
 # to list the dependency's destination directory.
 
 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",
   "sourceforge_url": "http://%(repo)s.svn.sourceforge.net/svnroot/%(repo)s",
   "webkit_trunk": "http://svn.webkit.org/repository/webkit/trunk",
   "nacl_trunk": "http://src.chromium.org/native_client/trunk",
@@ skipping 497 matching lines @@
       ((Var("googlecode_url") % "linux-syscall-support") + "/trunk/lss@" +
        Var("lss_revision")),
 
     "src/third_party/openssl":
       "/trunk/deps/third_party/openssl@157142",
 
     "src/third_party/WebKit/Tools/gdb":
       Var("webkit_trunk") + "/Tools/gdb@" + Var("webkit_revision"),
 
     "src/third_party/gold":
-      "/trunk/deps/third_party/gold@149858",
+      "/trunk/deps/third_party/gold@168091",
 
     "src/third_party/libmtp":
       "/trunk/deps/third_party/libmtp@167836",
 
     # Used on Linux only. CrOS already has a copy.
     "src/third_party/mtpd/source":
       Var("chromiumos_git") + "/platform/mtpd.git" +
       "@85d2ce42e73ca9afeffba3552a35a8d4b01b9c22",
 
     # Used on Linux only. CrOS already has a copy.
@@ skipping 100 matching lines @@
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     "pattern": ".",
     "action": ["python", "src/build/gyp_chromium"],
   },
   {
     # Check for landmines (reasons to clobber the build).
     "pattern": ".",
     "action": ["python", "src/build/landmines.py"],
   },
 ]