add NodeViewWrapper and NodeViewContent component

packages/vue-3/src/NodeViewContent.ts

@@ -0,0 +1,25 @@
+import { h, defineComponent } from 'vue'
+
+export const NodeViewContent = defineComponent({
+  props: {
+    as: {
+      type: String,
+      default: 'div',
+    },
+  },
+
+  inject: ['editable'],
+
+  render() {
+    return h(
+      this.as, {
+        style: {
+          whiteSpace: 'pre-wrap',
+        },
+        'data-node-view-content': '',
+        // @ts-ignore (https://github.com/vuejs/vue-next/issues/3031)
+        contenteditable: this.editable.value,
+      },
+    )
+  },
+})