Revert "A temporary fix for combined expression test in vector_arithmetics"
Revert "A temporary fix for combined expression test in vector_arithmetics"

This reverts commit 9e243394fbfaf32153033749fccfc7e75484f532.

kapadia/vexcl,ddemidov/vexcl,Poulpy21/vexcl,kapadia/vexcl,ddemidov/vexcl,Poulpy21/vexcl,Poulpy21/vexcl