Introduce initial plumbing for type promotion in fasta.

pkg/front_end/testcases/implicit_scope_test.dart.outline.expect

Index: pkg/front_end/testcases/implicit_scope_test.dart.outline.expect
diff --git a/pkg/front_end/testcases/implicit_scope_test.dart.outline.expect b/pkg/front_end/testcases/implicit_scope_test.dart.outline.expect
new file mode 100644
index 0000000000000000000000000000000000000000..5b631c6e1960da365d9a575b2e9ffb8b7f7f0d57
--- /dev/null
+++ b/pkg/front_end/testcases/implicit_scope_test.dart.outline.expect
@@ -0,0 +1,14 @@
+library;
+import self as self;
+import "dart:core" as core;
+
+class ImplicitScopeTest extends core::Object {
+  constructor •() → void
+    ;
+  static method alwaysTrue() → core::bool
+    ;
+  static method testMain() → dynamic
+    ;
+}
+static method main() → dynamic
+  ;