Remove some styles that are now useless after the position style was changed.

tp-dialog.js

@@ -54,25 +54,17 @@ class TpDialog extends EventHelpers(LitElement) {
           pointer-events: all;
           display: flex;
           flex-direction: column;
+          overflow: hidden;
         }
-
+        
         dialog:not([open]) {
           display: none;
         }
 
-        /* Only clip/scroll once the dialog has been explicitly sized via resize. */
-        :host([constrained]) dialog {
-          overflow: hidden;
-        }
-
         .scroll-wrapper {
           flex: 1;
           box-sizing: border-box;
           min-height: 0;
-          overflow: visible;
-        }
-
-        :host([constrained]) .scroll-wrapper {
           overflow: auto;
         }