update

src/core/wrapper/layout/flex/flex.horizontal.js

@@ -34,7 +34,7 @@ BI.FlexHorizontalLayout = BI.inherit(BI.Layout, {
         w.element.css({
             position: "relative"
         });
-        if (BI.contains([BI.HorizontalAlign.Left, BI.HorizontalAlign.Right], o.horizontalAlign)) {
+        if (o.horizontalAlign !== BI.HorizontalAlign.Stretch) {
             w.element.css({
                 "flex-shrink": "0"
             });

src/core/wrapper/layout/flex/flex.vertical.js

@@ -33,7 +33,7 @@ BI.FlexVerticalLayout = BI.inherit(BI.Layout, {
         w.element.css({
             position: "relative"
         });
-        if (o.verticalAlign === BI.VerticalAlign.Top || o.verticalAlign === BI.VerticalAlign.Bottom) {
+        if (o.verticalAlign !== BI.VerticalAlign.Stretch) {
             w.element.css({
                 "flex-shrink": "0"
             });

src/core/wrapper/layout/flex/wrapper/flex.wrapper.horizontal.js

@@ -35,7 +35,7 @@ BI.FlexWrapperHorizontalLayout = BI.inherit(BI.Layout, {
         w.element.css({
             position: "relative"
         });
-        if (o.horizontalAlign === BI.HorizontalAlign.Left || o.horizontalAlign === BI.HorizontalAlign.Right) {
+        if (o.horizontalAlign !== BI.HorizontalAlign.Stretch) {
             w.element.css({
                 "flex-shrink": "0"
             });

src/core/wrapper/layout/flex/wrapper/flex.wrapper.vertical.js

@@ -35,7 +35,7 @@ BI.FlexWrapperVerticalLayout = BI.inherit(BI.Layout, {
         w.element.css({
             position: "relative"
         });
-        if (o.verticalAlign === BI.VerticalAlign.Top || o.verticalAlign === BI.VerticalAlign.Bottom) {
+        if (o.verticalAlign !== BI.VerticalAlign.Stretch) {
             w.element.css({
                 "flex-shrink": "0"
             });