Switched from AM.getFocusedStackId() to getFocusedStackInfo() API.

Old API was removed in favor of the new one.

Test: builds.
Change-Id: Iadf6ec74a14516ecf18ee7cbd4ce20a63959d5fa
diff --git a/service/src/com/android/car/SystemActivityMonitoringService.java b/service/src/com/android/car/SystemActivityMonitoringService.java
index 2ff4e0e..4744ae5 100644
--- a/service/src/com/android/car/SystemActivityMonitoringService.java
+++ b/service/src/com/android/car/SystemActivityMonitoringService.java
@@ -208,7 +208,12 @@
         }
         int focusedStackId = -1;
         try {
-            focusedStackId = mAm.getFocusedStackId();
+            // TODO(b/66955160): Someone on the Auto-team should probably re-work the code in the
+            // synchronized block below based on this new API.
+            final StackInfo focusedStackInfo = mAm.getFocusedStackInfo();
+            if (focusedStackInfo != null) {
+                focusedStackId = focusedStackInfo.stackId;
+            }
         } catch (RemoteException e) {
             Log.e(CarLog.TAG_AM, "cannot getFocusedStackId", e);
             return;
@@ -251,16 +256,9 @@
     }
 
     public StackInfo getFocusedStackForTopActivity(ComponentName activity) {
-        int focusedStackId = -1;
-        try {
-            focusedStackId = mAm.getFocusedStackId();
-        } catch (RemoteException e) {
-            Log.e(CarLog.TAG_AM, "cannot getFocusedStackId", e);
-            return null;
-        }
         StackInfo focusedStack;
         try {
-            focusedStack = mAm.getStackInfo(focusedStackId);
+            focusedStack = mAm.getFocusedStackInfo();
         } catch (RemoteException e) {
             Log.e(CarLog.TAG_AM, "cannot getFocusedStackId", e);
             return null;