Fixed ComboBox - setSelectedIndex out of bounce when there are no values. #253

(cherry picked from commit b167be8)

Author: kevzlou7979

src/main/java/gwt/material/design/addins/client/combobox/MaterialComboBox.java

@@ -511,11 +511,13 @@ protected Option buildOption(String text, T value) {
      */
     public void setSelectedIndex(int selectedIndex) {
         this.selectedIndex = selectedIndex;
-        T value = values.get(selectedIndex);
-        if (value != null) {
-            $(listbox.getElement()).val(keyFactory.generateKey(value)).trigger("change.select2", selectedIndex);
-        } else {
-            GWT.log("Value index is not found.", new IndexOutOfBoundsException());
+        if (values.size() > 0) {
+            T value = values.get(selectedIndex);
+            if (value != null) {
+                $(listbox.getElement()).val(keyFactory.generateKey(value)).trigger("change.select2", selectedIndex);
+            } else {
+                GWT.log("Value index is not found.", new IndexOutOfBoundsException());
+            }
         }
     }