  We develop the theory of hydrodynamic electron transport in a long-range
disorder potential for conductors in which the underlying electron liquid lacks
Galilean invariance. For weak disorder, we express the transport coefficients
of the system in terms of the intrinsic kinetic coefficients of the electron
liquid and the correlation function of the disorder potential. We apply these
results to analyze the doping and temperature dependence of transport
coefficients of graphene devices. We show that at charge neutrality, long-range
disorder increases the conductivity of the system above the intrinsic value.
The enhancement arises from the predominantly vortical hydrodynamic flow caused
by local deviations from charge neutrality. Its magnitude is inversely
proportional to the shear viscosity of the electron liquid and scales as the
square of the disorder correlation radius. This is qualitatively different from
the situation away from charge neutrality. In that case, the flow is
predominantly potential, and produces negative viscous contributions to the
conductivity, which are proportional to the sum of shear and bulk viscosities,
and inversely proportional to the square of disorder correlation radius.
