Repro-code for a problem of phantomjs PDF generation

On Windows 7 pro, if I configured a custom font size, I have gotten a wrong result of phantomjs' PDF generation.

(in Japanese)

Probably this is the same window in English.

Repro Step

1. npm install
2. npm test
3. Open result.pdf

It would print a bounding box of A4. The box size is specified in millimeters.

.bounding-box-of-A4 {
    display: block;
    position: absolute;
    top: 0;
    left: 0;
    width: calc(210mm - 1px);
    height: calc(297mm - 1px);
    padding: 4px;
    box-sizing: border-box;
    border: 3px solid red;
}

Then:

• In the custom font size is 100% (default), it generated expected.pdf.
• In the custom font size is 125%, it generated wrong.pdf. This is too small.