Add latency metrics for recents gesture

Pass the touch down time to RecentsAnimation#startRecentsActivity.

Bug: 169221287
Test: Enable statsd log: "adb shell cmd stats print-logs"
      Touch gesture navigation bar.
      adb logcat | grep statsd | grep "(48)"
      The line may contain 0x100000->4[I] 0x110000->20[I]
      that means 4=by recents and 20=latency 20ms.
Change-Id: I81ee804895b7712f4d925736f5b4694c11a12cbe
(cherry picked from commit 63623967b8)

quickstep/src/com/android/quickstep/AbsSwipeUpHandler.java

@@ -1476,6 +1476,11 @@ public abstract class AbsSwipeUpHandler<T extends StatefulActivity<?>, Q extends
         mGestureEndCallback = gestureEndCallback;
     }
 
+    @Override
+    public long getStartTouchTime() {
+        return mTouchTimeMs;
+    }
+
     protected void linkRecentsViewScroll() {
         SurfaceTransactionApplier.create(mRecentsView, applier -> {
             mTransformParams.setSyncTransactionApplier(applier);

quickstep/src/com/android/quickstep/RecentsAnimationCallbacks.java

@@ -160,5 +160,12 @@ public class RecentsAnimationCallbacks implements
          * Callback made when a task started from the recents is ready for an app transition.
          */
         default void onTaskAppeared(RemoteAnimationTargetCompat appearedTaskTarget) {}
+
+        /**
+         * The time in milliseconds of the touch event that starts the recents animation.
+         */
+        default long getStartTouchTime() {
+            return 0;
+        }
     }
 }

quickstep/src/com/android/quickstep/TaskAnimationManager.java

@@ -50,7 +50,7 @@ public class TaskAnimationManager implements RecentsAnimationCallbacks.RecentsAn
     public void preloadRecentsAnimation(Intent intent) {
         // Pass null animation handler to indicate this start is for preloading
         UI_HELPER_EXECUTOR.execute(() -> ActivityManagerWrapper.getInstance()
-                .startRecentsActivity(intent, null, null, null, null));
+                .startRecentsActivity(intent, 0, null, null, null));
     }
 
     /**
@@ -119,10 +119,11 @@ public class TaskAnimationManager implements RecentsAnimationCallbacks.RecentsAn
                 }
             }
         });
+        final long eventTime = listener.getStartTouchTime();
         mCallbacks.addListener(gestureState);
         mCallbacks.addListener(listener);
         UI_HELPER_EXECUTOR.execute(() -> ActivityManagerWrapper.getInstance()
-                .startRecentsActivity(intent, null, mCallbacks, null, null));
+                .startRecentsActivity(intent, eventTime, mCallbacks, null, null));
         gestureState.setState(STATE_RECENTS_ANIMATION_INITIALIZED);
         return mCallbacks;
     }