Bug in AppBarLayout: wrong title behavior when initially collapsed - title

Question

I use typical AppBarLayout-CollapsingToolbarLayout-Toolbar bundle, and it works ok. But when I add app:expanded="false" or appBarLayout.setExpanded(false) before collapsingToolbarLayout.setTitle(), I have behavior shown in video below.
https://youtu.be/OgSJomzYmek
Here is layout:
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/coordinator_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true">
<android.support.design.widget.AppBarLayout
android:id="#+id/appbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
app:expanded="false"
android:theme="#style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.CollapsingToolbarLayout
android:id="#+id/collapsing_toolbar"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<ImageView
android:id="#+id/action_bar_image"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fitsSystemWindows="true"
android:scaleType="centerCrop"
android:src="#drawable/img_nature"
app:layout_collapseMode="parallax" />
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:elevation="4dp"
app:layout_collapseMode="pin" />
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
<include layout="#layout/content_main" />
<android.support.design.widget.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
app:backgroundTint="#color/colorPrimary"
app:layout_anchorGravity="bottom|right|end" />
</android.support.design.widget.CoordinatorLayout>
It must be bug in support library.
Is there solution to correctly collapse toolbar, or any workaround?
Update 1.
Have found "solution". In short:
Override CollapsingToolbarLayout onLayout
onLayout(changed, ...) {
if (changed) super.onLayout(true, ...);
}
Nothing more to override. Than use this custom CollapsingToolbarLayout instead of from support library one.
Do not understand why, but this is necessary.
In Activity
appBarLayout.post(... here first call of appBarLayout.setCollapsed() ... )
Do not use AppBarLayout until it completely measured and laid out.
Update 2.
Update 1 not works perfectly. Much better solution - works ok, at least for a while:
Another solution, seems works perfect, at least for a while...
public class Toolbar extends android.support.v7.widget.Toolbar {
private Integer offset = null;
public Toolbar(Context context) {
super(context);
}
public Toolbar(Context context, AttributeSet attrs) {
super(context, attrs);
}
public Toolbar(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
#Override
public void offsetTopAndBottom(int offset) {
super.offsetTopAndBottom(offset);
if (this.offset == null)
this.offset = offset;
}
#Override
public int getTitleMarginTop() {
return offset == null ? super.getTitleMarginTop() : -getTop() + offset + super.getTitleMarginTop();
}
#Override
public int getTitleMarginBottom() {
return offset == null ? super.getTitleMarginBottom() : getTop() - offset + super.getTitleMarginBottom();
}
}
That's all.
When ABL's setExpanded is called, it follows to CTL's onLayout: getDescendantRect and then mCollapsingTextHelper.setCollapsedBounds.
At this moment getDescendantRect calculates base absolute position for title. And calculated position, I suppose, has error - it's shifted on (CTL height - Window inset - Toolbar height). The code above corrects this error.