libs/editor/WordPressEditor/src/main/res/layout-v19/editor_webview.xml

<?xml version="1.0" encoding="utf-8"?>
<org.wordpress.android.editor.EditorWebView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    />