Link to PDF file (or attach file here):
https://issues.apache.org/jira/secure/attachment/12650283/000004_ShadingPatternTextPDF.pdf

Configuration:
- Web browser and its version: FF 51.0.1 32bit
- Operating system and its version: W7
- PDF.js version: latest

Steps to reproduce the problem:
display file

What is the expected behavior? (add screenshot)
![ok](https://cloud.githubusercontent.com/assets/6665575/23339534/5ff2de9c-fc25-11e6-837e-0fdaf81b4ca9.png)

What went wrong? (add screenshot)
![nok](https://cloud.githubusercontent.com/assets/6665575/23339536/63f7a37e-fc25-11e6-813c-cc218cc4def3.png)

possibly similar problem:
https://www.pdflib.com/fileadmin/pdflib/Cookbook/pdf/color_gradient.pdf (shaded text completely missing)
https://issues.apache.org/jira/secure/attachment/12630566/pslib-shading.pdf (page 4, part of text missing)
https://issues.apache.org/jira/secure/attachment/12652009/pattern-shading-2-4-idMatrix.pdf (some text missing)
https://issues.apache.org/jira/secure/attachment/12652010/pattern-shading-2-4-noMatrix.pdf (some text missing)

}
    if (i < totalChunks) {
      elemsInThisChunk = width * partialChunkHeight * 4;
      dest.set(src.subarray(srcPos, srcPos + elemsInThisChunk));
      if (hasTransferMaps) {
        for (let k = 0; k < elemsInThisChunk; k += 4) {
          if (transferMapRed) {
            dest[k + 0] = transferMapRed[dest[k + 0]];
          }
          if (transferMapGreen) {
            dest[k + 1] = transferMapGreen[dest[k + 1]];
          }
          if (transferMapBlue) {
            dest[k + 2] = transferMapBlue[dest[k + 2]];
          }
        }
      }
      ctx.putImageData(chunkImgData, 0, j);
    }
  } else if (imgData.kind === ImageKind.RGB_24BPP) {
    
    const hasTransferMaps = !!(
      transferMapRed ||
      transferMapGreen ||
      transferMapBlue
    );
    thisChunkHeight = FULL_CHUNK_HEIGHT;
    elemsInThisChunk = width * thisChunkHeight;
    for (i = 0; i < totalChunks; i++) {
      if (i >= fullChunks) {