accounts/abi: fixed broken types slice testcases

Check for slice in type as well and adapted test case as arrays
also store its types.

accounts/abi/type.go

@@ -94,7 +94,7 @@ func NewType(t string) (typ Type, err error) {
 		// Altough we know that this is an array, we cannot return
 		// as we don't know the type of the element, however, if it
 		// is still an array, then don't determine the type.
-		if typ.Elem.IsArray {
+		if typ.Elem.IsArray || typ.Elem.IsSlice {
 			return typ, nil
 		}
 	}
@@ -117,7 +117,12 @@ func NewType(t string) (typ Type, err error) {
 		varSize = 256
 		t += "256"
 	}
-	typ.stringKind = t
+
+	// only set stringKind if not array or slice, as for those,
+	// the correct string type has been set
+	if !(typ.IsArray || typ.IsSlice) {
+		typ.stringKind = t
+	}
 
 	switch varType {
 	case "int":