Roll DEPS for gyp to r1921

DEPS

 # This file is automatically processed to create .DEPS.git which is the file
 # that gclient uses under git.
 #
 # See http://code.google.com/p/chromium/wiki/UsingGit
 #
 # To test manually, run:
 #   python tools/deps2git/deps2git.py -o .DEPS.git -w <gclientdir>
 # where <gcliendir> is the absolute path to the directory containing the
 # .gclient file (the parent of "src").
 #
@@ skipping 126 matching lines @@
   "src/third_party/libc++abi/trunk":
     Var("llvm_url") + "/libcxxabi/trunk@" + Var("libcxxabi_revision"),
 
   "src/third_party/snappy/src":
     (Var("googlecode_url") % "snappy") + "/trunk@80",
 
   "src/tools/grit":
     (Var("googlecode_url") % "grit-i18n") + "/trunk@167",
 
   "src/tools/gyp":
-    (Var("googlecode_url") % "gyp") + "/trunk@1919",
+    (Var("googlecode_url") % "gyp") + "/trunk@1921",
 
   "src/tools/swarming_client":
     Var("chromium_git") + "/external/swarming.client.git@" +
         Var("swarming_revision"),
 
   "src/v8":
     (Var("googlecode_url") % "v8") + "/" + Var("v8_branch") + "@" +
     Var("v8_revision"),
 
   "src/native_client":
@@ skipping 609 matching lines @@
                 "-s", "src/build/linux/bin/eu-strip.sha1",
     ],
   },
   {
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     "name": "gyp",
     "pattern": ".",
     "action": ["python", "src/build/gyp_chromium"],
   },
 ]