fix(b-modal): solve body padding not being removed (#5771)

* update dom.js

* update

* update modal-manager.js

Author: Hiws

src/components/modal/helpers/modal-manager.js

@@ -159,29 +159,29 @@ const ModalManager = /*#__PURE__*/ Vue.extend({
         // Adjust fixed content padding
         /* istanbul ignore next: difficult to test in JSDOM */
         selectAll(Selector.FIXED_CONTENT).forEach(el => {
-          const actualPadding = getStyle(el, 'paddingRight')
+          const actualPadding = getStyle(el, 'paddingRight') || ''
           setAttr(el, 'data-padding-right', actualPadding)
           setStyle(el, 'paddingRight', `${toFloat(getCS(el).paddingRight, 0) + scrollbarWidth}px`)
           body._paddingChangedForModal.push(el)
         })
         // Adjust sticky content margin
         /* istanbul ignore next: difficult to test in JSDOM */
         selectAll(Selector.STICKY_CONTENT).forEach(el => /* istanbul ignore next */ {
-          const actualMargin = getStyle(el, 'marginRight')
+          const actualMargin = getStyle(el, 'marginRight') || ''
           setAttr(el, 'data-margin-right', actualMargin)
           setStyle(el, 'marginRight', `${toFloat(getCS(el).marginRight, 0) - scrollbarWidth}px`)
           body._marginChangedForModal.push(el)
         })
         // Adjust <b-navbar-toggler> margin
         /* istanbul ignore next: difficult to test in JSDOM */
         selectAll(Selector.NAVBAR_TOGGLER).forEach(el => /* istanbul ignore next */ {
-          const actualMargin = getStyle(el, 'marginRight')
+          const actualMargin = getStyle(el, 'marginRight') || ''
           setAttr(el, 'data-margin-right', actualMargin)
           setStyle(el, 'marginRight', `${toFloat(getCS(el).marginRight, 0) + scrollbarWidth}px`)
           body._marginChangedForModal.push(el)
         })
         // Adjust body padding
-        const actualPadding = getStyle(body, 'paddingRight')
+        const actualPadding = getStyle(body, 'paddingRight') || ''
         setAttr(body, 'data-padding-right', actualPadding)
         setStyle(body, 'paddingRight', `${toFloat(getCS(body).paddingRight, 0) + scrollbarWidth}px`)
       }