Adjust grid item layouts to match mocks.

<?xml version="1.0" encoding="utf-8"?>

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<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <item

        android:state_activated="true"

        android:color="?android:attr/colorAccent"

        android:alpha="0.1" />

    <item

        android:state_enabled="false"

        android:color="?android:attr/colorBackground"

        android:alpha="0.5" />

    <item

        android:color="@android:color/transparent" />

</selector>