Revert "Show in action bar when composing plain text message"

This reverts commit 04f2c3f367.

app/src/main/java/eu/faircode/email/FragmentCompose.java

@@ -776,7 +776,6 @@ public class FragmentCompose extends FragmentBase {
     public void onPrepareOptionsMenu(Menu menu) {
         super.onPrepareOptionsMenu(menu);
 
-        menu.findItem(R.id.menu_plain_icon).setVisible(state == State.LOADED && plain_only);
         menu.findItem(R.id.menu_zoom).setVisible(state == State.LOADED);
         menu.findItem(R.id.menu_media_toolbar).setVisible(state == State.LOADED);
         menu.findItem(R.id.menu_clear).setVisible(state == State.LOADED);

app/src/main/res/menu/menu_compose.xml

@@ -1,13 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <menu xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto">
-    <item
-        android:id="@+id/menu_plain_icon"
-        android:icon="@drawable/baseline_notes_24"
-        android:title="@string/title_send_plain_text"
-        android:visible="false"
-        app:showAsAction="always" />
-
     <item
         android:id="@+id/menu_zoom"
         android:icon="@drawable/baseline_format_size_24"