MediaProjectionPermissionActivity: Don't use app icons.

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

    android:insetLeft="2.5dp"

    android:insetRight="2.5dp">

    <vector android:width="24dp"

            android:height="24dp"

            android:viewportWidth="24.0"

            android:viewportHeight="24.0">

        <path android:fillColor="#FF000000" android:pathData="M1,18v3h3C4,19.34 2.66,18 1,18zM1,14v2c2.76,0 5,2.24 5,5h2C8,17.13 4.87,14 1,14zM1,10v2c4.97,0 9,4.03 9,9h2C12,14.92 7.07,10 1,10zM21,3H3C1.9,3 1,3.9 1,5v3h2V5h18v14h-7v2h7c1.1,0 2,-0.9 2,-2V5C23,3.9 22.1,3 21,3z"/>

        <path android:fillColor="#FF0000" android:pathData="M19,7H5v1.63c3.96,1.28 7.09,4.41 8.37,8.37H19V7z"/>

    </vector>

</inset>

        mDialog = new AlertDialog.Builder(this)

                .setTitle(dialogTitle)

                .setIcon(aInfo.loadIcon(packageManager))

                .setIcon(R.drawable.ic_media_projection_permission)

                .setMessage(message)

                .setPositiveButton(R.string.media_projection_action_text, this)

                .setNegativeButton(android.R.string.cancel, this)