Stub out Skia AVX and HSW opts.

skia/ext/SkOpts_avx_stub.cc

Index: skia/ext/SkOpts_avx_stub.cc
diff --git a/skia/ext/SkOpts_avx_stub.cc b/skia/ext/SkOpts_avx_stub.cc
new file mode 100644
index 0000000000000000000000000000000000000000..3fdf872aea66acd021bbf5b1b5cd1283d2670ce9
--- /dev/null
+++ b/skia/ext/SkOpts_avx_stub.cc
@@ -0,0 +1,10 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This is SkOpts_avx.cpp, stubbed out to do nothing.
+
+namespace SkOpts {
+    void Init_avx();
+    void Init_avx() {}
+}