Fix #83589: Remove Tooltips on Gizmo Mouse Down

Currently tooltips on gizmo parts can pop up while holding your mouse
down, unlike other UI elements. And they don't disappear until a few
pixels into a drag. This PR solves both by removing tooltips on mouse
down on a gizmo part.

Pull Request: https://projects.blender.org/blender/blender/pulls/132576

source/blender/windowmanager/intern/wm_event_system.cc

@@ -3183,6 +3183,11 @@ static eHandlerActionFlag wm_handlers_do_gizmo_handler(bContext *C,
   BLI_assert(gzmap != nullptr);
   wmGizmo *gz = wm_gizmomap_highlight_get(gzmap);
 
+  if (gz && ISMOUSE(event->type) && event->val == KM_PRESS) {
+    /* Remove any tooltips on mouse down. #83589 */
+    WM_tooltip_clear(C, CTX_wm_window(C));
+  }
+
   /* Needed so UI blocks over gizmos don't let events fall through to the gizmos,
    * noticeable for the node editor - where dragging on a node should move it, see: #73212.
    * note we still allow for starting the gizmo drag outside, then travel 'inside' the node. */