Move libvpx from DEPS to src

third_party/libvpx/source/libvpx/vp8/encoder/treewriter.c

Index: third_party/libvpx/source/libvpx/vp8/encoder/treewriter.c
diff --git a/third_party/libvpx/source/libvpx/vp8/encoder/treewriter.c b/third_party/libvpx/source/libvpx/vp8/encoder/treewriter.c
new file mode 100644
index 0000000000000000000000000000000000000000..ef25f670b3a4b5b422186d6fc6a944af814ffd93
--- /dev/null
+++ b/third_party/libvpx/source/libvpx/vp8/encoder/treewriter.c
@@ -0,0 +1,43 @@
+/*
+ *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+
+#include "treewriter.h"
+
+static void cost(
+    int *const C,
+    vp8_tree T,
+    const vp8_prob *const P,
+    int i,
+    int c
+)
+{
+    const vp8_prob p = P [i>>1];
+
+    do
+    {
+        const vp8_tree_index j = T[i];
+        const int d = c + vp8_cost_bit(p, i & 1);
+
+        if (j <= 0)
+            C[-j] = d;
+        else
+            cost(C, T, P, j, d);
+    }
+    while (++i & 1);
+}
+void vp8_cost_tokens(int *c, const vp8_prob *p, vp8_tree t)
+{
+    cost(c, t, p, 0, 0);
+}
+void vp8_cost_tokens2(int *c, const vp8_prob *p, vp8_tree t,int start)
+{
+    cost(c, t, p, start, 0);
+}