Update more directories under src/ to follow C++11 style rule for {virtual,override}.

src/opts/SkXfermode_opts_arm_neon.h

Index: src/opts/SkXfermode_opts_arm_neon.h
diff --git a/src/opts/SkXfermode_opts_arm_neon.h b/src/opts/SkXfermode_opts_arm_neon.h
index cc8c76d1eda7296843fd2f47b3d7c14504a6d418..206892edd6d22cf414b3b4bb3427ff118f0f0298 100644
--- a/src/opts/SkXfermode_opts_arm_neon.h
+++ b/src/opts/SkXfermode_opts_arm_neon.h
@@ -1,3 +1,10 @@
+/*
+ * Copyright 2015 Google Inc.

[tfarina, 2015/04/27 00:30:03]

This was necessary because I got:

** Presubmit ERRORS **
src/opts/SkXfermode_opts_arm_neon.h is missing a correct copyright header.

[mtklein, 2015/04/27 13:29:40]

I don't actually recall who wrote this file.  Better leave this off for now and
just tell the presubmit to shush.

[tfarina, 2015/04/27 14:04:53]

Done.

+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
 #ifndef SkXfermode_opts_arm_neon_DEFINED
 #define SkXfermode_opts_arm_neon_DEFINED
 
@@ -9,10 +16,10 @@ public:
                             void* procSIMD)
             : INHERITED(rec, mode), fProcSIMD(procSIMD) {}
 
-    virtual void xfer32(SkPMColor dst[], const SkPMColor src[], int count,
-                        const SkAlpha aa[]) const override;
-    virtual void xfer16(uint16_t* SK_RESTRICT dst, const SkPMColor* SK_RESTRICT src,
-                        int count, const SkAlpha* SK_RESTRICT aa) const override;
+    void xfer32(SkPMColor dst[], const SkPMColor src[], int count,
+                const SkAlpha aa[]) const override;
+    void xfer16(uint16_t* SK_RESTRICT dst, const SkPMColor* SK_RESTRICT src,
+                int count, const SkAlpha* SK_RESTRICT aa) const override;
 
     SK_TO_STRING_OVERRIDE()