Let Home activity restart during first few crashes

After we get to the rate-limit, we wind up on the

  "Home App keeps stopping
   App info
   Close app"

screen like we're supposed to.

Bug: 148087283
Test: adb shell kill -11 `adb shell pidof {launcher}`
Change-Id: I85874c2e4ad7098f87f1dbe6d0430b244852478b

services/core/java/com/android/server/wm/ActivityStack.java

@@ -2588,6 +2588,13 @@ class ActivityStack extends Task {
         if (r == null || r.app != app) {
             return null;
         }
+        if (r.isActivityTypeHome() && mAtmService.mHomeProcess == app) {
+            // Home activities should not be force-finished as we have nothing else to go
+            // back to. AppErrors will get to it after two crashes in MIN_CRASH_INTERVAL.
+            Slog.w(TAG, "  Not force finishing home activity "
+                    + r.intent.getComponent().flattenToShortString());
+            return null;
+        }
         Slog.w(TAG, "  Force finishing activity "
                 + r.intent.getComponent().flattenToShortString());
         Task finishedTask = r.getTask();