title: TabLayoutMediator not preserving TabItem attributes
body: <p>I have a simple setup using ViewPager2 and TabLayout with preset TabItems:</p>
  
  <pre><code>...
  
          &lt;com.google.android.material.tabs.TabLayout
              android:id="@+id/tabs"
              android:layout_width="0dp"
              android:layout_height="64dp"
              app:tabTextColor="@color/c0696D7"
              app:layout_constraintEnd_toEndOf="parent"
              app:layout_constraintStart_toEndOf="@+id/palettesToggle"
              app:layout_constraintTop_toTopOf="parent"
              app:tabBackground="@color/cEEEEEE"
              app:tabIndicatorColor="@color/cFFFFFF"
              app:tabGravity="fill"
              app:tabUnboundedRipple="true"
              app:tabIconTint="@color/palettes_icon_tint"
              app:tabIndicatorGravity="stretch"
              app:tabMode="fixed"&gt;
  
              &lt;com.google.android.material.tabs.TabItem android:icon="@drawable/palettes_layers" /&gt;
  
              &lt;com.google.android.material.tabs.TabItem android:icon="@drawable/palettes_view" /&gt;
  
              &lt;com.google.android.material.tabs.TabItem android:icon="@drawable/palettes_properties" /&gt;
  
              &lt;com.google.android.material.tabs.TabItem android:icon="@drawable/palettes_blocks" /&gt;
  
              &lt;com.google.android.material.tabs.TabItem android:icon="@drawable/palettes_blocks" /&gt;
  
              &lt;com.google.android.material.tabs.TabItem android:icon="@drawable/palettes_settings" /&gt;
  
          &lt;/com.google.android.material.tabs.TabLayout&gt;
  
          &lt;androidx.viewpager2.widget.ViewPager2
              android:id="@+id/viewPager"
              android:layout_width="match_parent"
              android:layout_height="0dp"
              app:layout_constraintBottom_toBottomOf="parent"
              app:layout_constraintEnd_toEndOf="parent"
              app:layout_constraintStart_toStartOf="parent"
              app:layout_constraintTop_toBottomOf="@+id/tabs" /&gt;
  
  ...
  </code></pre>
  
  <p>and the following wiring code:</p>
  
  <pre><code>TabLayoutMediator(tabs, viewPager) { tab, position -&gt;
  
          }.attach()
  </code></pre>
  
  <p>The following setup ignores the <code>TabItem</code> icon attribute, and I see empty tabs. It seems that <code>TabLayoutMediator</code> completely overrides the defined xml attributes and i must reset those attributes as part of the <code>TabConfigurationStrategy</code> callback.
  Am I missing something?   </p>