fix warning from scalar --> int32 conversion

BUG=

Review URL: https://codereview.appspot.com/7065050

git-svn-id: http://skia.googlecode.com/svn/trunk@7061 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/animator/SkDisplayEvent.cpp b/src/animator/SkDisplayEvent.cpp
index 52c874b..c926a8a 100644
--- a/src/animator/SkDisplayEvent.cpp
+++ b/src/animator/SkDisplayEvent.cpp
@@ -174,7 +174,7 @@
         return;
     maker.fEvents.addEvent(this);
     if (kind == kOnEnd) {
-        bool found = maker.find(target.c_str(), &fTarget);
+        SkDEBUGCODE(bool found = ) maker.find(target.c_str(), &fTarget);
         SkASSERT(found);
         SkASSERT(fTarget && fTarget->isAnimate());
         SkAnimateBase* animate = (SkAnimateBase*) fTarget;