Update media controls layout

Changes to match S mocks
- corner radius to match notifications
- solid background for device chip
- bigger album art

By default this only shows the icon for app/device, but this can be
changed with flags:

adb shell setprop persist.sysui.qs_media_show_app_name true
adb shell setprop persist.sysui.qs_media_show_device_name true
adb shell am crash com.android.systemui

Bug: 176177555
Test: visual
Test: atest MediaControlPanelTest
Change-Id: I76c3130df252baee3f5d3009f9098f77bf115f3e