MAGETWO-91657: Advanced pricing the bulk discounts by percentage returns error when set

- Added new validation rule for percentage value;

Author: Alexey Yakimovich

app/code/Magento/Catalog/Ui/DataProvider/Product/Form/Modifier/TierPrice.php

@@ -154,9 +154,7 @@ private function getUpdatedTierPriceStructure(array $priceMeta)
                                     'addbefore' => '%',
                                     'validation' => [
                                         'required-entry' => true,
-                                        'validate-number' => true,
-                                        'validate-greater-than-zero' => true,
-                                        'less-than-equals-to' => 100
+                                        'validate-positive-percent-decimal' => true
                                     ],
                                     'visible' => $firstOption
                                         && $firstOption['value'] == ProductPriceOptionsInterface::VALUE_PERCENT,

app/code/Magento/Ui/view/base/web/js/lib/validation/rules.js

@@ -686,6 +686,24 @@ define([
             },
             $.mage.__('The value is not within the specified range.')
         ],
+        'validate-positive-percent-decimal': [
+            function (value) {
+                var numValue;
+
+                if (utils.isEmptyNoTrim(value) || !/^\s*-?\d*(\.\d*)?\s*$/.test(value)) {
+                    return false;
+                }
+
+                numValue = utils.parseNumber(value);
+
+                if (isNaN(numValue)) {
+                    return false;
+                }
+
+                return utils.isBetween(numValue, 0.01, 100);
+            },
+            $.mage.__('Please enter a valid percentage discount value greater than 0.')
+        ],
         'validate-digits': [
             function (value) {
                 return utils.isEmptyNoTrim(value) || !/[^\d]/.test(value);