Merge "Always use Spp to generate SettingsPage in Gallery"

...droid/settingslib/spa/gallery/button/ActionButtonsPage.kt

...src/com/android/settingslib/spa/gallery/page/ChartPage.kt

...rc/com/android/settingslib/spa/gallery/page/FooterPage.kt

.../android/settingslib/spa/gallery/page/IllustrationPage.kt

...om/android/settingslib/spa/gallery/page/LoadingBarPage.kt

...m/android/settingslib/spa/gallery/page/ProgressBarPage.kt

...android/settingslib/spa/gallery/page/SettingsPagerPage.kt

...rc/com/android/settingslib/spa/gallery/page/SliderPage.kt

...ngslib/spa/gallery/preference/MainSwitchPreferencePage.kt

...ettingslib/spa/gallery/preference/SwitchPreferencePage.kt

...b/spa/gallery/preference/TwoTargetSwitchPreferencePage.kt

...src/com/android/settingslib/spa/gallery/ui/SpinnerPage.kt