Add (failing) test case for mixin type parameters.

sdk/lib/_internal/compiler/implementation/resolution/members.dart

Index: sdk/lib/_internal/compiler/implementation/resolution/members.dart
diff --git a/sdk/lib/_internal/compiler/implementation/resolution/members.dart b/sdk/lib/_internal/compiler/implementation/resolution/members.dart
index b9ca6ff20d700e8cb6b0b437bf4bb8d79a0fa86e..93193c44677e9c43fe6f3c9479b8ec382b6cd2d3 100644
--- a/sdk/lib/_internal/compiler/implementation/resolution/members.dart
+++ b/sdk/lib/_internal/compiler/implementation/resolution/members.dart
@@ -2873,6 +2873,10 @@ class ClassResolverVisitor extends TypeDefinitionVisitor {
     compiler.ensure(element != null);
     compiler.ensure(element.resolutionState == STATE_STARTED);
 
+    InterfaceType type = element.computeType(compiler);
+    scope = new TypeDeclarationScope(scope, element);
+    resolveTypeVariableBounds(node.typeParameters);
+
     // Generate anonymous mixin application elements for the
     // intermediate mixin applications (excluding the last).
     DartType supertype = resolveSupertype(element, node.superclass);