Rollup merge of #103865 - compiler-errors:fallback-has-occurred-tracking, r=eholk

Move `fallback_has_occurred` state tracking to `FnCtxt`

Removes a ton of callsites that defaulted to `false`

compiler/rustc_const_eval/src/transform/check_consts/check.rs

@@ -765,7 +765,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> {
 
                         let errors = ocx.select_all_or_error();
                         if !errors.is_empty() {
-                            infcx.err_ctxt().report_fulfillment_errors(&errors, None, false);
+                            infcx.err_ctxt().report_fulfillment_errors(&errors, None);
                         }
                     }
 
@@ -831,7 +831,6 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> {
                                         obligation.clone(),
                                         &obligation,
                                         &e,
-                                        false,
                                     );
                                 }