Pull gn binary

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://svn.code.sf.net/p/%(repo)s/code",
   "webkit_trunk": "http://src.chromium.org/blink/trunk",
   "nacl_trunk": "http://src.chromium.org/native_client/trunk",
@@ skipping 589 matching lines @@
   {
     # Update LASTCHANGE.blink. This is also run by export_tarball.py in
     # src/tools/export_tarball - please keep them in sync.
     "name": "lastchange",
     "pattern": ".",
     "action": ["python", "src/build/util/lastchange.py",
                "-s", "src/third_party/WebKit",
                "-o", "src/build/util/LASTCHANGE.blink"],
   },
   {
+    # Pull GN binaries. This needs to be before running GYP below.
+    "name": "gn",
+    "pattern": "\\.sha1$",
+    "action": [ "download_from_google_storage",
+                "--directory",
+                "--recursive",
+                "--bucket", "chromium-gn",
+                "src/tools/gn/bin",
+    ],
+  },
+  {
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     "name": "gyp",
     "pattern": ".",
     "action": ["python", "src/build/gyp_chromium"],
   },
   {
     # Check for landmines (reasons to clobber the build).
     "name": "landmines",
     "pattern": ".",
     "action": ["python", "src/build/landmines.py"],
   },
 ]