Renamed a few methods in ActivityRecord (42/n).

This is in preparation for having the ActivityRecord class
extend AppWindowToken where name distinction will be important.
There is no functional change in this CL.

ActivityRecord.realActivity -> mActivityComponent
ActivityRecord.userId -> mUserId
ActivityRecord.getTask() -> getTaskRecord()
ActivityRecord.getStack() -> getActivityStack()
ActivityRecord.service -> mAtmService
WindowContainer.mService -> mWmService

Bug: 80414790
Test: Existing tests pass.
Change-Id: Ie5788db7f2e823c7d5b64c7ce6eaade1c19c4dcd
diff --git a/services/core/java/com/android/server/wm/ActivityMetricsLogger.java b/services/core/java/com/android/server/wm/ActivityMetricsLogger.java
index 16df52d..12690a9 100644
--- a/services/core/java/com/android/server/wm/ActivityMetricsLogger.java
+++ b/services/core/java/com/android/server/wm/ActivityMetricsLogger.java
@@ -254,7 +254,7 @@
             type = getTransitionType(info);
             processRecord = findProcessForActivity(launchedActivity);
             processName = launchedActivity.processName;
-            userId = launchedActivity.userId;
+            userId = launchedActivity.mUserId;
             launchedActivityShortComponentName = launchedActivity.shortComponentName;
             activityRecordIdHashCode = System.identityHashCode(launchedActivity);
             this.windowsFullyDrawnDelayMs = windowsFullyDrawnDelayMs;
@@ -520,7 +520,7 @@
         if (info.launchedActivity != activityRecord) {
             return;
         }
-        final TaskRecord t = activityRecord.getTask();
+        final TaskRecord t = activityRecord.getTaskRecord();
         final SomeArgs args = SomeArgs.obtain();
         args.arg1 = t;
         args.arg2 = activityRecord;
@@ -893,7 +893,7 @@
             builder.addTaggedData(FIELD_ACTIVITY_RECORD_TARGET_ACTIVITY, r.info.targetActivity);
             builder.addTaggedData(FIELD_ACTIVITY_RECORD_FLAGS, r.info.flags);
             builder.addTaggedData(FIELD_ACTIVITY_RECORD_REAL_ACTIVITY,
-                    r.realActivity.toShortString());
+                    r.mActivityComponent.toShortString());
             builder.addTaggedData(FIELD_ACTIVITY_RECORD_SHORT_COMPONENT_NAME, r.shortComponentName);
             builder.addTaggedData(FIELD_ACTIVITY_RECORD_PROCESS_NAME, r.processName);
             builder.addTaggedData(FIELD_ACTIVITY_RECORD_IS_FULLSCREEN, r.fullscreen ? 1 : 0);