Add flac into root BUILD.gn

All hail GN. oRZ

BUG=none

Review URL: https://codereview.chromium.org/263503003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@268265 0039d316-1c4b-4281-b951-d872f2087c98

BUILD.gn

@@ -38,6 +38,7 @@ group("root") {
     #"//sdch",
     "//skia",
     #"//third_party/WebKit/Source/platform",
+    "//third_party/flac",
     "//third_party/icu",
     "//third_party/leveldatabase",
     "//third_party/libpng",

DEPS

@@ -229,7 +229,7 @@ deps = {
     "/trunk/deps/third_party/libjpeg_turbo@263594",
 
   "src/third_party/flac":
-    "/trunk/deps/third_party/flac@222897",
+    "/trunk/deps/third_party/flac@266977",
 
   "src/third_party/pyftpdlib/src":
     (Var("googlecode_url") % "pyftpdlib") + "/trunk@977",