The ornamental design for a double walldrinkingglass, as shown and described.
FIG. 1 is a top perspective view of my new design for a double wall drinking glass;
FIG. 2 is a bottom perspective view thereof;
FIG. 3 is a front elevational view thereof, with the rear elevational view, left-side elevational view, and right-side elevational view being identical thereto;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof; and,
FIG. 6 is a sectional view thereof, taken along line 6-6 in FIG. 3.
The broken line arrows in FIG. 3 depict cross-sectional indicia and form no part of the claimed design.