includegraphics inside a TikZ node with XeLaTeX is incorrectly positioned when width or height is given

includegraphics inside a TikZ node with XeLaTeX is incorrectly positioned
when width or height is given

Consider the following code:
\documentclass{article}
\usepackage{tikz}
\begin{document}
a\includegraphics[height=100pt]{example-image-10x16}b
\begin{tikzpicture}
\node[anchor=south west] at (0,0)
{a\includegraphics[height=100pt]{example-image-10x16}b};
\fill[red] (0,0) circle[radius=.1];
\end{tikzpicture}
\end{document}
Run with pdflatex and it compiles just fine. Run with xelatex and the
image in the node is displaced. It appears to be where the included
graphic is located, since the a and b are always in the correct place. It
also has something to do with the explicit height=100pt since removing
that also fixes the problem (width=<something> also causes the problem to
occur).

What's happening?
How can I make it stop?



Note that the following are related:
Wrong positioning of images inside tikzpicture with XeLaTeX
Switching from PDFLaTeX to XeLaTeX is messing with my pgftext coordinates
but I'm already in the situation of the answers given there.
Nor does the answer to Centering full-page Tikz image on page without
margins with xelatex? work.



Edit: Following on from David and Harish's comments, I updated TL2013 and
PGF. With the PGF that comes with TL2013 then it compiles correctly. With
the CVS version of PGF then it does not. So the problem appears to lie
with the PGF code for xelatex. I also discovered that the page changed
from A4 paper (TL version of PGF) to letter paper (CVS version). As a
Brit, my TL is set to produce A4 by default. Manually putting in a4paper
changes the paper size back to A4, but doesn't correct the image
displacement. So my guess is that the error is in PGF's driver file for
XeTeX.