Android Studio Layout Error: invalid region.op - only intersect and difference are allowed

I'm getting an error from Android Studio in the Preview Section of my layout, which is very simple. The error is "invalid region.op - only intersect and difference are allowed". The layout only has 2 nested linear layouts, and it stopped rendering when the 2nd linear layout was added.

Here is my layout:

<LinearLayout 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"
android:background="@color/colorBackgroundGray"
android:orientation="vertical">

<android.support.v7.widget.RecyclerView
    android:id="@+id/recycler_view"
    android:layout_width="match_parent"
    android:layout_height="120dp"
    android:layout_below="@id/desc_textview" />

<TextView
    android:id="@+id/qty_label"
    android:layout_width="300dp"
    android:layout_height="wrap_content"
    android:layout_below="@id/recycler_view"
    android:layout_marginStart="8dp"
    android:layout_marginTop="8dp"
    android:gravity="center"
    android:text="Scan Lot Number: "
    android:textColor="@color/colorBlack"
    android:textSize="18sp" />

<EditText
    android:id="@+id/lot_num_edit"
    android:layout_width="300dp"
    android:layout_height="wrap_content"
    android:layout_below="@id/qty_label"
    android:layout_marginStart="8dp"
    android:layout_marginTop="8dp"
    android:background="@color/colorYellow"
    android:gravity="center_vertical"
    android:paddingStart="8dp"
    android:textColor="@color/colorBlack"
    android:textSize="18sp"
    tools:text="Lot Number" />

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="16dp"
    android:orientation="horizontal">

    <Button
        android:id="@+id/exit_button"
        android:layout_width="100dp"
        android:layout_height="60dp"
        android:layout_gravity="center_horizontal"
        android:layout_marginStart="8dp"
        android:layout_marginEnd="8dp"
        android:layout_weight="1"
        android:background="@drawable/button_yellow"
        android:onClick="onExitClick"
        android:text="Exit"
        android:textColor="@color/colorBlack"
        android:textSize="20sp" />


    <Button
        android:id="@+id/ok_button"
        android:layout_width="100dp"
        android:layout_height="60dp"
        android:layout_gravity="center_horizontal"
        android:layout_marginStart="8dp"
        android:layout_marginEnd="8dp"
        android:layout_weight="1"
        android:background="@drawable/button_gray"
        android:onClick="onOkayClick"
        android:text="OK"
        android:textColor="@color/colorBlack"
        android:textSize="20sp" />

    <Button
        android:id="@+id/cancel_button"
        android:layout_width="100dp"
        android:layout_height="60dp"
        android:layout_gravity="center_horizontal"
        android:layout_marginStart="8dp"
        android:layout_marginEnd="8dp"
        android:layout_weight="1"
        android:background="@drawable/button_gray"
        android:onClick="onCancelClick"
        android:text="Cancel"
        android:textColor="@color/colorBlack"
        android:textSize="20sp" />

    <Button
        android:id="@+id/continue_button"
        android:layout_width="100dp"
        android:layout_height="60dp"
        android:layout_gravity="center_horizontal"
        android:layout_marginStart="8dp"
        android:layout_marginEnd="8dp"
        android:layout_weight="1"
        android:background="@drawable/button_gray"
        android:onClick="onContinueClick"
        android:text="Continue"
        android:textColor="@color/colorBlack"
        android:textSize="20sp" />

</LinearLayout>
</LinearLayout>