MAGETWO-44405: Unable to change item cart qty from item configure page

- Merge remote-tracking branch 'origin/MAGETWO-44405' into PR
- Conflicts: app/code/Magento/Msrp/view/base/web/js/msrp.js

Author: Volodymyr Zaets

app/code/Magento/Catalog/view/frontend/requirejs-config.js

@@ -11,8 +11,6 @@ var config = {
             relatedProducts:        'Magento_Catalog/js/related-products',
             upsellProducts:         'Magento_Catalog/js/upsell-products',
             productListToolbarForm: 'Magento_Catalog/js/product/list/toolbar',
-            tierPrice:              'Magento_Catalog/js/tier-price',
-            addToCart:              'Magento_Msrp/js/msrp',
             catalogGallery:         'Magento_Catalog/js/gallery',
             priceBox:               'Magento_Catalog/js/price-box',
             priceOptionDate:        'Magento_Catalog/js/price-option-date',

app/code/Magento/Checkout/view/frontend/templates/cart/item/configure/updatecart.phtml

@@ -22,7 +22,7 @@
             </div>
             <?php endif; ?>
             <div class="actions">
-                <button type="button"
+                <button type="submit"
                         title="<?php /* @escapeNotVerified */ echo $buttonTitle ?>"
                         class="action primary tocart"
                         id="product-updatecart-button">

app/code/Magento/Msrp/view/base/web/js/msrp.js

@@ -226,6 +226,29 @@ define([
         closePopup: function ($elem) {
             $elem.dropdownDialog('close');
             $(document).off('mouseup');
+        },
+
+        /**
+         * Handler for addToCart action
+         */
+        _addToCartSubmit: function () {
+            this.element.trigger('addToCart', this.element);
+
+            if (this.element.data('stop-processing')) {
+                return false;
+            }
+
+            if (this.options.addToCartButton) {
+                $(this.options.addToCartButton).click();
+
+                return false;
+            }
+
+            if (this.options.addToCartUrl) {
+                $('.mage-dropdown-dialog > .ui-dialog-content').dropdownDialog('close');
+            }
+            $(this.options.cartForm).submit();
+
         }
     });