Bug 759535 - Cleanup unused variable from Bug 733553. r=joe

image/src/RasterImage.cpp

@@ -1456,7 +1456,6 @@ RasterImage::AddSourceData(const char *aBuffer, PRUint32 aCount)
   // so that there's no gap for anything to miss us.
   if (mBytesDecoded == 0) {
     // Our previous state may have been animated, so let's clean up
-    bool wasAnimating = mAnimating;
     if (mAnimating) {
       StopAnimation();
       mAnimating = false;