[SB][Call chip] Update call chip to use icon from notification.

This change:
1) Has notification/icon/IconManager.kt create a new icon for the call
   chip. The icon is based on Notification.smallIcon.
2) Updates OngoingCallController to pass that icon to CallChipViewModel.
3) Updates CallChipViewModel to use the icon if the flag is enabled.
4) Updates CollapsedStatusBarViewBinder to use that icon if it exists,
   and manipulates all the view paddings such that things look correct.
   This is required because Notification.smallIcons are required to
   embed their own padding, and we need to account for that.

Note that this change only works if two other flags are also enabled:
- status_bar_use_repos_for_call_chip (due to b/355288215)
- status_bar_screen_sharing_chips (due to too much eng effort required
  to re-implement all these changes in OngoingCallController#updateChip)

Bug: 354930838
Flag: com.android.systemui.status_bar_call_chip_notification_icon

Test: With new flag off, start calls from various apps -> verify chip
always shows default phone icon with good padding
Test: With new flag on, start calls and receive calls from various apps
-> verify chip icon always matches the icon shown in the call
notification small icon slot with good padding
Test: Do screen record, share, and cast -> verify chip shows the right
icons with good padding
Test: Start call then change font size, display size, wallpaper color ->
verify chip updates correctly

Test: atest OngoingCallControllerTest CallChipViewModelTest

Change-Id: I2b0b35cb87041638b5e1c0e2ac5658ca8230b2b4
diff --git a/packages/SystemUI/aconfig/systemui.aconfig b/packages/SystemUI/aconfig/systemui.aconfig
index 9df739c..37581e5 100644
--- a/packages/SystemUI/aconfig/systemui.aconfig
+++ b/packages/SystemUI/aconfig/systemui.aconfig
@@ -403,6 +403,13 @@
 }
 
 flag {
+    name: "status_bar_call_chip_notification_icon"
+    namespace: "systemui"
+    description: "Use the small icon set on the notification for the status bar call chip"
+    bug: "354930838"
+}
+
+flag {
     name: "compose_bouncer"
     namespace: "systemui"
     description: "Use the new compose bouncer in SystemUI"