Missed a case where we should not have flexGrow

src/navigators/__tests__/__snapshots__/TabNavigator-test.js.snap

@@ -138,10 +138,10 @@ exports[`TabNavigator renders successfully 1`] = `
           <View
             style={
               Array [
+                false,
                 Object {
                   "flexGrow": 1,
                 },
-                false,
               ]
             }
           >

src/views/TabView/TabBarBottom.js

@@ -101,6 +101,8 @@ class TabBarBottom extends React.PureComponent {
       return null;
     }
 
+    const horizontal = this._shouldUseHorizontalTabs();
+
     return (
       <TabBarIcon
         position={position}
@@ -110,8 +112,8 @@ class TabBarBottom extends React.PureComponent {
         renderIcon={renderIcon}
         scene={scene}
         style={[
-          styles.icon,
-          this._shouldUseHorizontalTabs() && styles.horizontalIcon,
+          horizontal && styles.horizontalIcon,
+          showLabel !== false && !horizontal && styles.icon,
         ]}
       />
     );