Add min/max value enum to Java

C++ bindings have a kMinValue and kMaxValue in mojo
enums. This adds the same to the Java bindings.

BUG=899802

Change-Id: Ic3dd6ca5b665c6ed6adbd5ffcc80e93573dc51c6
Reviewed-on: https://chromium-review.googlesource.com/c/1305193Reviewed-by: Ken Rockot <rockot@google.com>
Commit-Queue: Becca Hughes <beccahughes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#603917}

mojo/public/tools/bindings/generators/java_templates/enum_definition.tmpl

@@ -15,6 +15,13 @@ public {{ 'static ' if not top_level }}final class {{enum|name}} {
     public static final int {{field|name}} = {{enum_value(enum, field, loop.index0)}};
 {% endfor %}
 
+{%-   if enum.min_value is not none %}
+    public static final int MIN_VALUE = (int) ({{enum.min_value}});
+{%-   endif %}
+{%-   if enum.max_value is not none %}
+    public static final int MAX_VALUE = (int) ({{enum.max_value}});
+{%-   endif %}
+
     private static final boolean IS_EXTENSIBLE = {% if enum.extensible %}true{% else %}false{% endif %};
 
     public static boolean isKnownValue(int value) {