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/effects/SkTableColorFilter.cpp b/src/effects/SkTableColorFilter.cpp
index ad34fbb..ff30636 100644
--- a/src/effects/SkTableColorFilter.cpp
+++ b/src/effects/SkTableColorFilter.cpp
@@ -181,10 +181,10 @@
     SkASSERT(size <= sizeof(storage));
     buffer.readByteArray(storage);
 
-    size_t raw = SkPackBits::Unpack8(storage, size, fStorage);
+    SkDEBUGCODE(size_t raw = ) SkPackBits::Unpack8(storage, size, fStorage);
 
     SkASSERT(raw <= sizeof(fStorage));
-    size_t count = gCountNibBits[fFlags & 0xF];
+    SkDEBUGCODE(size_t count = gCountNibBits[fFlags & 0xF]);
     SkASSERT(raw == count * 256);
 }