Remove stray semicolons.

Turns out function declarations don't end in semicolons...

BUG=skia:

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2720

No public API changes.
TBR=reed@google.com

Change-Id: I72b56d52e1ff7fa6e89c295b0de8c46599791ebb
Reviewed-on: https://skia-review.googlesource.com/2720
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Klein <mtklein@chromium.org>
diff --git a/tests/RefCntTest.cpp b/tests/RefCntTest.cpp
index 3691593..d5be621 100644
--- a/tests/RefCntTest.cpp
+++ b/tests/RefCntTest.cpp
@@ -334,7 +334,7 @@
 
         struct StructB : public SkRefCnt {
             sk_sp<StructA> a;
-            ~StructB() override {}; // Some clang versions don't emit this implicitly.
+            ~StructB() override {} // Some clang versions don't emit this implicitly.
         };
 
         // Create a reference cycle.