Check if image width or height are zero before proceeding.

core/fxcodec/jbig2/JBig2_Image.cpp

Index: core/fxcodec/jbig2/JBig2_Image.cpp
diff --git a/core/fxcodec/jbig2/JBig2_Image.cpp b/core/fxcodec/jbig2/JBig2_Image.cpp
index b8cb21165bd6e64f9799aa6c232770bbcefed17a..2071221cd1e5116da17f0959cf4fa1afa0b1cff2 100644
--- a/core/fxcodec/jbig2/JBig2_Image.cpp
+++ b/core/fxcodec/jbig2/JBig2_Image.cpp
@@ -23,7 +23,7 @@ CJBig2_Image::CJBig2_Image(int32_t w, int32_t h)
       m_nHeight(0),
       m_nStride(0),
       m_bOwnsBuffer(true) {
-  if (w < 0 || h < 0 || w > kMaxImagePixels)
+  if (w <= 0 || h <= 0 || w > kMaxImagePixels)
     return;
 
   int32_t stride_pixels = (w + 31) & ~31;