Compatibility with Rotations.jl

I have been trying to get Zygote to work along with RigidBodyDynamics.jl for computing Jacobians and Hessians of nonlinear functions. I have been trying to compute Jacobians using this function:

# Source: https://github.com/FluxML/Zygote.jl/issues/98#issuecomment-497739021
function zygote_jacobian(f, x)
    y = f(x)
    n = length(y)
    m = length(x)
    T = eltype(y)
    j = Array{T, 2}(undef, n, m)
    for i in 1:n
        j[i, :] .= gradient(x -> f(x)[i], x)[1]
    end
    return j
end

This method seems to be working for not-so-complicated functions. However, when I try to target functions using, e.g., Rotations.jl, I get the following error:

MethodError: no method matching (::getfield(Zygote, Symbol("##945#946")){Rotations.RotMatrix{3,Float64,9},StaticArrays.SArray{Tuple{3},Float64,1,3}})(::NamedTuple{(:data,),Tuple{Tuple{Float64,Nothing,Nothing}}})
Closest candidates are:
  #945(!Matched::AbstractArray{T,1} where T) at /home/henrique/.julia/packages/Zygote/bdE6T/src/lib/array.jl:207

Stacktrace:
 [1] (::getfield(Zygote, Symbol("##2365#back#947")){getfield(Zygote, Symbol("##945#946")){Rotations.RotMatrix{3,Float64,9},StaticArrays.SArray{Tuple{3},Float64,1,3}}})(::NamedTuple{(:data,),Tuple{Tuple{Float64,Nothing,Nothing}}}) at /home/henrique/.julia/packages/ZygoteRules/Jn4LO/src/adjoint.jl:48
 [2] * at /home/henrique/.julia/packages/RigidBodyDynamics/XgNGG/src/spatial/threevectors.jl:68 [inlined]
 [3] (::typeof(∂(*)))(::NamedTuple{(:v, :frame),Tuple{NamedTuple{(:data,),Tuple{Tuple{Float64,Nothing,Nothing}}},Nothing}}) at /home/henrique/.julia/packages/Zygote/bdE6T/src/compiler/interface2.jl:0
 [4] transform at /home/henrique/.julia/packages/RigidBodyDynamics/XgNGG/src/spatial/threevectors.jl:38 [inlined]
 [5] (::typeof(∂(transform)))(::NamedTuple{(:v, :frame),Tuple{NamedTuple{(:data,),Tuple{Tuple{Float64,Nothing,Nothing}}},Nothing}}) at /home/henrique/.julia/packages/Zygote/bdE6T/src/compiler/interface2.jl:0
 [6] forward_kinematics at ./In[11]:4 [inlined]
 [7] (::typeof(∂(forward_kinematics)))(::NamedTuple{(:data,),Tuple{Tuple{Float64,Nothing,Nothing}}}) at /home/henrique/.julia/packages/Zygote/bdE6T/src/compiler/interface2.jl:0
 [8] #3 at ./In[3]:8 [inlined]
 [9] (::typeof(∂(λ)))(::Float64) at /home/henrique/.julia/packages/Zygote/bdE6T/src/compiler/interface2.jl:0
 [10] (::getfield(Zygote, Symbol("##32#33")){typeof(∂(λ))})(::Float64) at /home/henrique/.julia/packages/Zygote/bdE6T/src/compiler/interface.jl:38
 [11] gradient(::Function, ::Array{Float64,1}) at /home/henrique/.julia/packages/Zygote/bdE6T/src/compiler/interface.jl:47
 [12] zygote_jacobian(::typeof(forward_kinematics), ::Array{Float64,1}) at ./In[3]:8
 [13] top-level scope at In[13]:1

Please confer this notebook for a full example that triggers the error shown above.

FluxML / Zygote.jl

Compatibility with Rotations.jl #370