Fix memory leaks in ImageThresholder::ThresholdToPix
Fix memory leaks in ImageThresholder::ThresholdToPix

tesseract-ocr/tesseract,tesseract-ocr/tesseract,amitdo/tesseract,amitdo/tesseract,amitdo/tesseract,tesseract-ocr/tesseract,tesseract-ocr/tesseract,tesseract-ocr/tesseract,amitdo/tesseract,amitdo/tesseract