IssueTracker

Library used: design
Version used: 23.4.0
Devices/Android versions reproduced on: Emulator with API 23 image


Setting setFitsSystemWindows in xml works:

XmlDeclaredActivity with following layout (of course not useful, but a quick sample):

```
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/coordinator_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true">

    <ImageView
        android:layout_width="match_parent"
        android:layout_height="80dp"
        android:background="@android:color/holo_orange_dark"
        android:fitsSystemWindows="true"
        android:scaleType="center"
        android:src="@android:drawable/sym_def_app_icon" />
</android.support.design.widget.CoordinatorLayout>
```

works as expected (see screenshot).

ProgrammaticallyActivity
```
public class ProgrammaticallyActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_programmatically);

        findViewById(R.id.coordinator_layout).setFitsSystemWindows(true);
    }
}
```
layout activity_programmatically idential to the above, except for no
```
    android:fitsSystemWindows="true"
```
at the CoordinatorLayout does not (see screenshot).


I understand the problem to be that window insets setup happens only in the constructor, in
```
        if (INSETS_HELPER != null) {
            INSETS_HELPER.setupForWindowInsets(this, new ApplyInsetsListener());
        }
```
Calls to setFitsSystemWindows do not perform the setup, if needed.


I haven't found a good way to patch this.