Zero jpeg_decompress_struct before calling jpeg_calc_output_dimensions().

src/codec/SkJpegCodec.cpp

Index: src/codec/SkJpegCodec.cpp
diff --git a/src/codec/SkJpegCodec.cpp b/src/codec/SkJpegCodec.cpp
index 6f7af49975d1d827953938a7e0b18a1d123d5849..a4ad76651797e1e99dd2c0742e97212d3896339b 100644
--- a/src/codec/SkJpegCodec.cpp
+++ b/src/codec/SkJpegCodec.cpp
@@ -188,6 +188,7 @@ SkISize SkJpegCodec::onGetScaledDimensions(float desiredScale) const {
 
     // Set up a fake decompress struct in order to use libjpeg to calculate output dimensions
     jpeg_decompress_struct dinfo;
+    sk_bzero(&dinfo, sizeof(dinfo));
     dinfo.image_width = this->getInfo().width();
     dinfo.image_height = this->getInfo().height();
     dinfo.global_state = DSTATE_READY;