Roll GYP to 1451. Changes:

r1449/r1450: Pass defines to midl.exe.
r1447: ninja windows: Add build.ninja variable to turn on dep_database.

r1448 was reverted in r1451.

BUG=140324

Review URL: https://chromiumcodereview.appspot.com/10823151

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@149792 0039d316-1c4b-4281-b951-d872f2087c98

DEPS

@@ -100,7 +100,7 @@ deps = {
     (Var("googlecode_url") % "grit-i18n") + "/trunk@63",
 
   "src/tools/gyp":
-    (Var("googlecode_url") % "gyp") + "/trunk@1446",
+    (Var("googlecode_url") % "gyp") + "/trunk@1451",
 
   "src/v8":
     (Var("googlecode_url") % "v8") + "/trunk@" + Var("v8_revision"),