input: reset view when pasting from primary

We’re already doing this for keyboard input, and regular clipboard
pastes.

CHANGELOG.md

@@ -80,6 +80,8 @@
 * Rendering of CSD borders when `csd.border-width > 0` and desktop
   scaling has been enabled.
 * Failure to launch when `exec(3)’:ed with an empty argv.
+* Pasting from the primary clipboard (mouse middle clicking) did not
+  reset the scrollback view to the bottom.
 
 
 ### Security

input.c

@@ -145,6 +145,7 @@ execute_binding(struct seat *seat, struct terminal *term,
 
     case BIND_ACTION_PRIMARY_PASTE:
         selection_from_primary(seat, term);
+        term_reset_view(term);
         return true;
 
     case BIND_ACTION_SEARCH_START: