Roll libvpx 254609:258445.

Picks up the suppression of -fstack-protector-all on iOS to avoid a crash.

BUG=3067
R=wu@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/10369004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5745 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/DEPS b/DEPS
index 28f6aae..6ff121e 100644
--- a/DEPS
+++ b/DEPS
@@ -78,7 +78,7 @@
     From("chromium_deps", "src/third_party/libsrtp"),
 
   "third_party/libvpx":
-    Var("chromium_trunk") + "/deps/third_party/libvpx@254609",
+    Var("chromium_trunk") + "/deps/third_party/libvpx@258445",
 
   "third_party/libyuv":
     (Var("googlecode_url") % "libyuv") + "/trunk@985",