Update expectations.

pkg/front_end/testcases/fallthrough.dart.direct.expect

 library;
 import self as self;
 import "dart:core" as core;
 
 static method main(core::List<core::String> args) → void {
   dynamic x = args.length;
   #L1:
   switch(x) {
     #L2:
     case 3:
       {
         x = 4;
-        throw new core::FallThroughError::•();
+        throw new core::FallThroughError::_create("pkg/front_end/testcases/fallthrough.dart", 4);
       }
     #L3:
     case 5:
       {
         break #L1;
       }
     #L4:
     case 6:
     case 7:
       {
         if(args.[](0).==("")) {
           break #L1;
         }
         else {
           return;
         }
-        throw new core::FallThroughError::•();
+        throw new core::FallThroughError::_create("pkg/front_end/testcases/fallthrough.dart", 8);
       }
     #L5:
     case 4:
       {
         break #L1;
       }
   }
 }