bug in view for words in a free group

[ThomasBreuer]

The following happens in GAP 4.10.2 as well as in the current master branch.

gap> f:= FreeGroup( ["x","y"] );;
gap> x:= f.1;;  y:= f.2;;
gap> w1:= y^7*x*y*x*y^3*x*y*x;
y^4*(y^2*(y*x)^2)^2
gap> w2:= y^-7*x*y^16;
y^-7*x*y^16
gap> w:= w1 * w2;
y^4*(y^2*y^16^2)^2*y^-7*x*y^16

(The way how w1 and w2 are viewed is correct, but the way w is viewed is wrong.)

[fingolfin]

This regression is also in GAP 4.9, but not in GAP 4.8, 4.7, 4.6. It was introduced before the HPC-GAP merge and the new build system. I'm now bisecting it.

[fingolfin]

The regression was introduced by commit b2d2bb2 (ping @hulpke)