Remove HRuntimeType scheme for function types.

pkg/compiler/lib/src/js_backend/checked_mode_helpers.dart

Index: pkg/compiler/lib/src/js_backend/checked_mode_helpers.dart
diff --git a/pkg/compiler/lib/src/js_backend/checked_mode_helpers.dart b/pkg/compiler/lib/src/js_backend/checked_mode_helpers.dart
index ab44766eea8b877bb925bed00bd66f5f0e6e846d..b05fe1fac1da9d366a768d23ed52dc3858f7f67d 100644
--- a/pkg/compiler/lib/src/js_backend/checked_mode_helpers.dart
+++ b/pkg/compiler/lib/src/js_backend/checked_mode_helpers.dart
@@ -89,6 +89,18 @@ class TypeVariableCheckedModeHelper extends CheckedModeHelper {
   }
 }
 
+class FunctionWithRepresentationCheckedModeHelper extends CheckedModeHelper {

[Emily Fortuna, 2017/02/25 00:26:02]

Can you add a comment here to explain what you mean by "WithRespresentation" (or
just reword the name of this class)

[sra1, 2017/02/28 05:16:03]

Done.

+  const FunctionWithRepresentationCheckedModeHelper(String name) : super(name);
+
+  CallStructure get callStructure => CallStructure.TWO_ARGS;
+
+  void generateAdditionalArguments(SsaCodeGenerator codegen,
+      HTypeConversion node, List<jsAst.Expression> arguments) {
+    codegen.use(node.typeRepresentation);
+    arguments.add(codegen.pop());
+  }
+}
+
 class SubtypeCheckedModeHelper extends CheckedModeHelper {
   const SubtypeCheckedModeHelper(String name) : super(name);
 
@@ -149,6 +161,8 @@ class CheckedModeHelpers {
     const TypeVariableCheckedModeHelper('assertSubtypeOfRuntimeType'),
     const PropertyCheckedModeHelper('propertyTypeCast'),
     const PropertyCheckedModeHelper('propertyTypeCheck'),
+    const FunctionWithRepresentationCheckedModeHelper('functionTypeCast'),
+    const FunctionWithRepresentationCheckedModeHelper('functionTypeCheck'),
   ];
 
   // Checked mode helpers indexed by name.
@@ -212,7 +226,9 @@ class CheckedModeHelpers {
           : 'assertSubtypeOfRuntimeType';
     }
 
-    if (type.isFunctionType) return null;
+    if (type.isFunctionType) {
+      return typeCast ? 'functionTypeCast' : 'functionTypeCheck';
+    }
 
     assert(invariant(NO_LOCATION_SPANNABLE, type.isInterfaceType,
         message: "Unexpected type: $type"));