Add DEPS files and run checkdeps in presubmit check

DEPS

 # Note: The buildbots evaluate this file with CWD set to the parent
 # directory and assume that the root of the checkout is in ./v8/, so
 # all paths in here must match this assumption.
 
 vars = {
   "chromium_trunk": "https://src.chromium.org/svn/trunk",
 
   "buildtools_revision": "83ed7189066fd9b4b9ea15ffc2d4ab6d2da62571",
 }
 
@@ skipping 13 matching lines @@
 deps_os = {
   "win": {
     "v8/third_party/cygwin":
       Var("chromium_trunk") + "/deps/third_party/cygwin@66844",
 
     "v8/third_party/python_26":
       Var("chromium_trunk") + "/tools/third_party/python_26@89111",
   }
 }
 
+include_rules = [
+  # Everybody can use some things.
+  "+include",
+  "+unicode",
+]
+
+# checkdeps.py shouldn't check for includes in these directories:
+skip_child_includes = [
+  "build",
+  "third_party",
+]
+
 hooks = [
   {
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     "pattern": ".",
     "action": ["python", "v8/build/gyp_v8"],
   },
 ]