Move activity-related methods to ActivityRecord

Moving methods that use and/or alter the internal state of
ActivityRecord from ActivityStack.

Bug: 137329632
Test: ActivityRecordTests ActivityStackTests
Change-Id: I92cea71a9e97d2f7c64547e844496beaf4a3a6d6
diff --git a/services/core/java/com/android/server/wm/RecentsAnimation.java b/services/core/java/com/android/server/wm/RecentsAnimation.java
index caa8363..1a8944a 100644
--- a/services/core/java/com/android/server/wm/RecentsAnimation.java
+++ b/services/core/java/com/android/server/wm/RecentsAnimation.java
@@ -149,8 +149,8 @@
             // traversal in non-stopped state (ViewRootImpl.mStopped) that would initialize more
             // things (e.g. the measure can be done earlier). The actual stop will be performed when
             // it reports idle.
-            targetStack.addToStopping(targetActivity, true /* scheduleIdle */,
-                    true /* idleDelayed */, "preloadRecents");
+            targetActivity.addToStopping(true /* scheduleIdle */, true /* idleDelayed */,
+                    "preloadRecents");
         }
     }