[groovy] get presentable text in GroovyExpressionTypeProvider.

It is needed to properly display `as`-coercion trait types e.g. `Foo as T1, T2` instead of `Foo`.

plugins/groovy/src/org/jetbrains/plugins/groovy/codeInsight/hint/GroovyExpressionTypeProvider.java

@@ -31,7 +31,7 @@ public class GroovyExpressionTypeProvider extends ExpressionTypeProvider<GrExpre
   @Override
   public String getInformationHint(@NotNull GrExpression element) {
     final PsiType type = element.getType();
-    return StringUtil.escapeXml(type == null ? "<unknown>" : type.getCanonicalText());
+    return StringUtil.escapeXml(type == null ? "<unknown>" : type.getPresentableText());
   }
 
   @NotNull