Once I changed Histogram2 to histogram2 (MATLAB is case sensitive), it works fine:
Xedges = [-Inf -2:0.4:2 Inf];
Yedges = [-Inf -2:0.4:2 Inf];
h = histogram2(x,y,Xedges,Yedges)
I suspect that your m-file is called Histogram2.m and that it's calling itself. It recurses deeper and deeper with no way to back out, until it eventually calls itself 500 times and throws that error you saw.
Correct the name to histogram2, and change the name of your m-file to something like test_histogram.m instead of Histogram2.m.