color leak in new array m code

[davidcarlisle]

Brief outline of the bug

color leaks due to the box re-arrangement in teh new m code corrupting the color stack

https://tex.stackexchange.com/questions/450726/different-behaviour-of-color-in-tabular-m-and-tabular-p/450729#450729
aa887.log

Minimal example showing the bug

\RequirePackage{latexbug} 
\documentclass[10pt]{article}

\usepackage{color}
\usepackage{array}%[=2016-10-06]

\begin{document}
    \begin{tabular}{|*{3}{>{\centering}p{1cm}|}}
        \hline \leavevmode\color{red}A&B&C\tabularnewline \hline
    \end{tabular}

    \begin{tabular}{|*{3}{>{\centering}m{1cm}|}}
        \hline \leavevmode\color{blue}A&B&C\tabularnewline \hline
    \end{tabular}

    Some blablah...
\end{document}

Log file (required) and possibly PDF file

[FrankMittelbach]

added a color group since $\vcenter ...$ is no longer used