Constrain Lockscreen smartspace to half screen for wide shade layout.

Also applied Kotlin formatting fixes. (Diff patch 1 and 2.)

Flag: EXEMPT bugfix
Fix: 375243612
Test: trigger sports card, check smartspace when clock is centered.
Test: SmartspaceSectionTest
Test: KeyguardSmartspaceViewModelTest
Change-Id: Ie52269fed4ee0d849068157391c409fb18ce9595