Is this a bug in Android support design Library?

Question

I just started to use the new Deisgn library from Google : 'com.android.support:design:22.2.0'

I use the FloatingActionButton and I have a small issue between Android below 5.0 and over 5.0. Watch the screenshot :

Android 4.4 :

Android 5.0 :

As you can see, on Android 4.4, there is a margin around the FAB. I think this is for displaying the shadow. But IT'S OVERSIZED ! So is it a bug (or a forget of Google) or just the normal behavior ?

The xml of the view hosting he fabs :

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="fr.freemo.freemo.activities.ListFreemoCityActivity">

<include
    android:id="@+id/toolbar"
    layout="@layout/view_toolbar" />


<FrameLayout
    android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_below="@+id/toolbar">

</FrameLayout>


<ProgressBar
    android:id="@+id/progressBar"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerHorizontal="true"
    android:layout_centerVertical="true" />

<android.support.design.widget.FloatingActionButton
    android:id="@+id/fab_add"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_alignParentEnd="true"
    android:layout_alignParentRight="true"
    android:layout_marginBottom="@dimen/margin_fab"
    android:layout_marginRight="@dimen/margin_fab"
    android:elevation="@dimen/fab_elevation_lollipop"
    android:src="@drawable/ic_action_new"
    app:backgroundTint="@color/color_app"
    app:fab_type="normal" />


<android.support.design.widget.FloatingActionButton
    android:id="@+id/fab_display"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_above="@+id/fab_add"
    android:layout_alignParentEnd="true"
    android:layout_alignParentRight="true"
    android:layout_marginBottom="@dimen/margin_fab"
    android:layout_marginRight="@dimen/margin_fab"
    android:elevation="@dimen/fab_elevation_lollipop"
    android:src="@drawable/ic_map_white"
    android:tint="@color/color_app"
    app:backgroundTint="@color/white"
    app:fab_type="normal" />

<android.support.design.widget.FloatingActionButton
    android:id="@+id/fab_display_list"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_above="@+id/fab_display"
    android:layout_alignParentEnd="true"
    android:layout_alignParentRight="true"
    android:layout_marginBottom="@dimen/margin_fab"
    android:layout_marginRight="@dimen/margin_fab"
    android:elevation="@dimen/fab_elevation_lollipop"
    android:src="@drawable/ic_action_list"
    android:tint="@color/color_app"
    android:visibility="invisible"
    app:backgroundTint="@color/white"
    app:fab_type="normal" />

<android.support.design.widget.FloatingActionButton
    android:id="@+id/fab_display_grid"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_above="@+id/fab_display_list"
    android:layout_alignParentRight="true"
    android:layout_marginBottom="@dimen/margin_fab"
    android:layout_marginRight="@dimen/margin_fab"
    android:elevation="@dimen/fab_elevation_lollipop"
    android:src="@drawable/ic_view_module_white"
    android:tint="@color/color_app"
    android:visibility="invisible"
    app:backgroundTint="@color/white"
    app:fab_type="normal" />
   </RelativeLayout>

Answer 1

It was an issue (check a bug report created by me: https://code.google.com/p/android/issues/detail?id=175330) and should be fixed in the future release of the support-design library.