Mark overridden destructors with 'override' and remove 'virtual'

This silences a new warning in clang 5.0

Change-Id: Ieb5b75a6ffed60107c3fd16075d2ecfd515b55e8
Reviewed-on: https://skia-review.googlesource.com/10006
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/bench/GMBench.h b/bench/GMBench.h
index 5e8b04ab46..c9ec80c643 100644
--- a/bench/GMBench.h
+++ b/bench/GMBench.h
@@ -18,7 +18,7 @@ class GMBench : public Benchmark {
 public:
     // Constructor takes ownership of the GM param.
     GMBench(skiagm::GM* gm);
-    virtual ~GMBench();
+    ~GMBench() override;
 
 protected:
     const char* onGetName() override;