The matrix used in the spec is column-major but Gfx::Matrix4x4 is
row-major so we need to transpose the values. This will fix internal
operations on that matrix. Because we also transposed the readonly
matrix property getters the matrix is again transposed when reading
so the JavaScript world only sees a column-major matrix.
Stop worrying about tiny OOMs. Work towards #20449.
While going through these, I also changed the function signature in many
places where returning ThrowCompletionOr<T> is no longer necessary.
