Revert "Support runtime check of function types."

sdk/lib/_internal/lib/foreign_helper.dart

Index: sdk/lib/_internal/lib/foreign_helper.dart
diff --git a/sdk/lib/_internal/lib/foreign_helper.dart b/sdk/lib/_internal/lib/foreign_helper.dart
index 3e8ac6374c78165acb0f57eaefe8fb9efbd82595..3cfe86a429bfeea72fd0c862aa5ad46a357c154b 100644
--- a/sdk/lib/_internal/lib/foreign_helper.dart
+++ b/sdk/lib/_internal/lib/foreign_helper.dart
@@ -161,9 +161,6 @@ String JS_OPERATOR_AS_PREFIX() {}
 /// Returns the name of the class `Object` in the generated code.
 String JS_OBJECT_CLASS_NAME() {}
 
-/// Returns the name of the class `Function` in the generated code.
-String JS_FUNCTION_CLASS_NAME() {}
-
 /**
  * Returns the field name used for determining if an object or its
  * interceptor has JavaScript indexing behavior.
@@ -174,44 +171,3 @@ String JS_IS_INDEXABLE_FIELD_NAME() {}
  * Returns the object corresponding to Namer.CURRENT_ISOLATE.
  */
 JS_CURRENT_ISOLATE() {}
-
-/// Returns the name used for generated function types on classes and methods.
-String JS_SIGNATURE_NAME() {}
-
-/// Returns the name used to tag function type representations in JavaScript.
-String JS_FUNCTION_TYPE_TAG() {}
-
-/**
- * Returns the name used to tag void return in function type representations
- * in JavaScript.
- */
-String JS_FUNCTION_TYPE_VOID_RETURN_TAG() {}
-
-/**
- * Returns the name used to tag return types in function type representations
- * in JavaScript.
- */
-String JS_FUNCTION_TYPE_RETURN_TYPE_TAG() {}
-
-/**
- * Returns the name used to tag required parameters in function type
- * representations in JavaScript.
- */
-String JS_FUNCTION_TYPE_REQUIRED_PARAMETERS_TAG() {}
-
-/**
- * Returns the name used to tag optional parameters in function type
- * representations in JavaScript.
- */
-String JS_FUNCTION_TYPE_OPTIONAL_PARAMETERS_TAG() {}
-
-/**
- * Returns the name used to tag named parameters in function type
- * representations in JavaScript.
- */
-String JS_FUNCTION_TYPE_NAMED_PARAMETERS_TAG() {}
-
-/**
- * Returns the global object, usually called encoded as [: $ :].
- */
-JS_GLOBAL_OBJECT() {}