Enumerate URIs of all types in type errors in order to help the user diagnose

runtime/vm/flow_graph_builder.cc

Index: runtime/vm/flow_graph_builder.cc
diff --git a/runtime/vm/flow_graph_builder.cc b/runtime/vm/flow_graph_builder.cc
index 4bf3ec999cf74a8a5df01081991a6e97871525bc..c97c353ecefcd0f63f953bda306cc197b90c0c12 100644
--- a/runtime/vm/flow_graph_builder.cc
+++ b/runtime/vm/flow_graph_builder.cc
@@ -1684,12 +1684,10 @@ void EffectGraphVisitor::BuildTypeCast(ComparisonNode* node) {
   ValueGraphVisitor for_value(owner());
   node->left()->Visit(&for_value);
   Append(for_value);
-  const String& dst_name = String::ZoneHandle(
-      Z, Symbols::New(Exceptions::kCastErrorDstName));
   if (CanSkipTypeCheck(node->token_pos(),
                        for_value.value(),
                        type,
-                       dst_name)) {
+                       Symbols::InTypeCast())) {
     ReturnValue(for_value.value());
     return;
   }