fix: Route name missing for routes that have children

With page structure like

```
pages/posts.vue
pages/posts/extra.vue
```

`posts.vue` is a parent route and `extra.vue` is a child route.
Former has `posts` name and latter has `posts_extra` name.
Removing name from parent route makes parent route inaccessible
through name and thus breaks internal functions like `localePath`
and `switchLocalePath`.

Fix by not removing names from routes.

And also checking if name exists at all before trying to add locale
as with some file structures, for example:

```
pages/posts.vue
pages/posts/index.vue
```

the parent `posts.vue` route has no name as `posts` name is assigned
to child and child is shown by default when going to /posts.
Trying to add locale in that case ended up with route named
`undefined_xx`.

Resolves #356

src/helpers/routes.js

@@ -72,12 +72,13 @@ exports.makeRoutes = (baseRoutes, {
         continue
       }
 
-      // Make localized route name
-      localizedRoute.name = name + routesNameSeparator + locale
+      // Make localized route name. Name might not exist on parent route if child has same path.
+      if (name) {
+        localizedRoute.name = name + routesNameSeparator + locale
+      }
 
       // Generate localized children routes if any
       if (route.children) {
-        delete localizedRoute.name
         localizedRoute.children = []
         for (let i = 0, length1 = route.children.length; i < length1; i++) {
           localizedRoute.children = localizedRoute.children.concat(buildLocalizedRoutes(route.children[i], { locales: [locale] }, true, isExtraRouteTree))
@@ -96,10 +97,11 @@ exports.makeRoutes = (baseRoutes, {
         if (!isChild) {
           const defaultRoute = { ...localizedRoute, path }
 
-          // Only routes without children have name
-          if (!defaultRoute.children) {
+          if (name) {
             defaultRoute.name = localizedRoute.name + routesNameSeparator + defaultLocaleRouteNameSuffix
-          } else {
+          }
+
+          if (defaultRoute.children) {
             // Recreate child routes with default suffix added
             defaultRoute.children = []
             for (const childRoute of route.children) {
@@ -109,7 +111,7 @@ exports.makeRoutes = (baseRoutes, {
           }
 
           routes.push(defaultRoute)
-        } else if (isChild && isExtraRouteTree) {
+        } else if (isChild && isExtraRouteTree && name) {
           localizedRoute.name += routesNameSeparator + defaultLocaleRouteNameSuffix
         }
       }

test/module.test.js

@@ -137,6 +137,17 @@ describe('basic', () => {
     })
   })
 
+  test('navigates to dynamic child route and checks path to other locale', async () => {
+    const window = await nuxt.renderAndGetWindow(url('/dynamicNested/1'))
+
+    const body = window.document.querySelector('body')
+    expect(body.textContent).toContain('Category')
+    expect(body.textContent).not.toContain('Subcategory')
+
+    // Will only work if navigated-to route has a name.
+    expect(window.$nuxt.switchLocalePath('fr')).toBe('/fr/imbrication-dynamique/1')
+  })
+
   test('/dynamicNested/1/2/3 contains link to /fr/imbrication-dynamique/1/2/3', async () => {
     const html = await get('/dynamicNested/1/2/3')
     expect(cleanUpScripts(html)).toMatchSnapshot()