Remove an as expression.

Change-Id: Iba2cc074da5fd052071a09a6bc4d985c0219d991
Reviewed-on: https://dart-review.googlesource.com/65031
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
diff --git a/pkg/analyzer/lib/src/dart/element/type.dart b/pkg/analyzer/lib/src/dart/element/type.dart
index 8514e4f..bc6ebcc 100644
--- a/pkg/analyzer/lib/src/dart/element/type.dart
+++ b/pkg/analyzer/lib/src/dart/element/type.dart
@@ -1274,7 +1274,7 @@
   }
 
   @override
-  ClassElement get element => super.element as ClassElement;
+  ClassElement get element => super.element;
 
   @override
   int get hashCode {
diff --git a/pkg/analyzer/lib/src/dart/resolver/inheritance_manager.dart b/pkg/analyzer/lib/src/dart/resolver/inheritance_manager.dart
index cb19d0f..024ff7b 100644
--- a/pkg/analyzer/lib/src/dart/resolver/inheritance_manager.dart
+++ b/pkg/analyzer/lib/src/dart/resolver/inheritance_manager.dart
@@ -240,8 +240,7 @@
       InterfaceType definingType) {
     // if the baseFunctionType is null, or does not have any parameters,
     // return it.
-    if (baseFunctionType == null ||
-        baseFunctionType.typeArguments.length == 0) {
+    if (baseFunctionType == null || baseFunctionType.typeArguments.isEmpty) {
       return baseFunctionType;
     }
     // First, generate the path from the defining type to the overridden member
@@ -691,7 +690,7 @@
         }
       }
     }
-    if (lookupMaps.length == 0) {
+    if (lookupMaps.isEmpty) {
       return null;
     }
     return lookupMaps;