Remove element from DynamicType.

sdk/lib/_internal/compiler/implementation/inferrer/concrete_types_inferrer.dart

Index: sdk/lib/_internal/compiler/implementation/inferrer/concrete_types_inferrer.dart
diff --git a/sdk/lib/_internal/compiler/implementation/inferrer/concrete_types_inferrer.dart b/sdk/lib/_internal/compiler/implementation/inferrer/concrete_types_inferrer.dart
index 358d74eec09e73cce214b49695cb804596e2b1e6..361d2f25c665903ed0ec0909c912ea31bdec8ca6 100644
--- a/sdk/lib/_internal/compiler/implementation/inferrer/concrete_types_inferrer.dart
+++ b/sdk/lib/_internal/compiler/implementation/inferrer/concrete_types_inferrer.dart
@@ -434,8 +434,6 @@ class ConcreteTypeSystem extends TypeSystem<ConcreteType> {
         return new TypeMask.nonNullSubclass(compiler.backend.numImplementation);
       } else if (element == compiler.backend.intImplementation) {
         return new TypeMask.nonNullSubclass(compiler.backend.intImplementation);
-      } else if (element == compiler.dynamicClass) {
-        return new TypeMask.nonNullSubclass(compiler.objectClass);
       } else {
         return new TypeMask.nonNullExact(element.declaration);
       }
@@ -495,14 +493,13 @@ class ConcreteTypeSystem extends TypeSystem<ConcreteType> {
     if (annotation.isVoid) return nullType;
     if (annotation.element == compiler.objectClass) return type;
     ConcreteType otherType;
-    if (annotation.kind == TypeKind.TYPEDEF
-        || annotation.kind == TypeKind.FUNCTION) {
+    if (annotation.isTypedef || annotation.isFunctionType) {
       otherType = functionType;
-    } else if (annotation.kind == TypeKind.TYPE_VARIABLE) {
+    } else if (annotation.isTypeVariable) {
       // TODO(polux): Narrow to bound.
       return type;
     } else {
-      assert(annotation.kind == TypeKind.INTERFACE);
+      assert(annotation.isInterfaceType);
       otherType = nonNullSubtype(annotation.element);
     }
     if (isNullable) otherType = otherType.union(nullType);
@@ -1799,7 +1796,7 @@ class ConcreteTypesInferrer
     // We trust the return type of native elements
     if (isNativeElement(element)) {
       var elementType = element.type;
-      assert(elementType.kind == TypeKind.FUNCTION);
+      assert(elementType.isFunctionType);
       return typeOfNativeBehavior(
           native.NativeBehavior.ofMethod(element, compiler));
     }