The ornamental design for a drinkingglass, as shown and described.
1. Drinking glass
1.1 : Front
1.2 : Top
1.3 : Bottom
1.4 : Perspective
1.5 : Reference view
1.6 : Cross sectional
The back view, the right view and the left view are omitted since they are same as the front view, respectively; reproduction 1.5 is a reference view which includes the two-dot chain lines showing a three-dimensional shape of the article surface, and does not form part of the claimed design; reproduction 1.6 is a cross-sectional view sectioned vertically at the center part of the front view.