From 94d1b4be17f607b17b20915b3adba6a1ef18a5ae Mon Sep 17 00:00:00 2001
From: Tony Wickham <twickham@google.com>
Date: Fri, 19 Jun 2020 17:42:18 -0500
Subject: [PATCH] Fix RecentsView scroll linking

- Reverts change from ag/11900651 that deferred setting
  mRecentsViewScrollLinked = true
- Instead, setCurrentPage(mCurrentPage) after updating layout rotation
  to ensure we recompute page scrolls before using them

Test:
- Auto rotate on, home rotation off, open Calculator in landscape,
  swipe up slowly and ensure it never turns invisible
- Quick switch from Calculator to Clock, start swiping directly up
  immediately after settling on Clock, ensure Calculator window
  remains at its scroll position to the side (b/159461591)

Fixes: 159461591
Change-Id: Iab92963cc6c33df42b77f5ccfa3932382e8f869a
---
 .../src/com/android/quickstep/BaseSwipeUpHandler.java        | 5 +----
 .../src/com/android/quickstep/views/RecentsView.java         | 2 ++
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/quickstep/recents_ui_overrides/src/com/android/quickstep/BaseSwipeUpHandler.java b/quickstep/recents_ui_overrides/src/com/android/quickstep/BaseSwipeUpHandler.java
index 9db6576765..02bae64274 100644
--- a/quickstep/recents_ui_overrides/src/com/android/quickstep/BaseSwipeUpHandler.java
+++ b/quickstep/recents_ui_overrides/src/com/android/quickstep/BaseSwipeUpHandler.java
@@ -121,10 +121,6 @@ public abstract class BaseSwipeUpHandler<T extends StatefulActivity<?>, Q extend
         });
 
         mRecentsView.setOnScrollChangeListener((v, scrollX, scrollY, oldScrollX, oldScrollY) -> {
-            // Wait until the first scroll event before applying scroll to taskViewSimulator.
-            // Since, by default the current/running task already centered, this ensures that we
-            // do not move the running task, in case RecentsView has not yet laid out completely.
-            mRecentsViewScrollLinked = true;
             if (moveWindowWithRecentsScroll()) {
                 updateFinalShift();
             }
@@ -132,6 +128,7 @@ public abstract class BaseSwipeUpHandler<T extends StatefulActivity<?>, Q extend
         runOnRecentsAnimationStart(() ->
                 mRecentsView.setRecentsAnimationTargets(mRecentsAnimationController,
                         mRecentsAnimationTargets));
+        mRecentsViewScrollLinked = true;
     }
 
     protected void startNewTask(Consumer<Boolean> resultCallback) {
diff --git a/quickstep/recents_ui_overrides/src/com/android/quickstep/views/RecentsView.java b/quickstep/recents_ui_overrides/src/com/android/quickstep/views/RecentsView.java
index 6380bbefa0..dd9eb19591 100644
--- a/quickstep/recents_ui_overrides/src/com/android/quickstep/views/RecentsView.java
+++ b/quickstep/recents_ui_overrides/src/com/android/quickstep/views/RecentsView.java
@@ -1656,6 +1656,8 @@ public abstract class RecentsView<T extends BaseActivity> extends PagedView impl
                     !mOrientationState.canLauncherRotate() && isInLandscape);
             resetPaddingFromTaskSize();
             requestLayout();
+            // Reapply the current page to update page scrolls.
+            setCurrentPage(mCurrentPage);
         }
     }