Revert "Keep scroll by keyboard after child focused node is removed"

This reverts commit 09a1f53e.

Sheriff: I suspect this is causing the LEAK failures here:
https://ci.chromium.org/p/chromium/builders/ci/WebKit%20Linux%20Trusty%20Leak/34655
https://test-results.appspot.com/data/layout_results/WebKit_Linux_Trusty_Leak/34655/webkit_layout_tests/layout-test-results/results.html


Original change's description:
> Keep scroll by keyboard after child focused node is removed
> 
> So far, scroll stops if focused child node is removed
> while scrolling parent node.
> This is because the event handler passes the |MousePressNode|.
> If focused child node(|MousePressNode|) is removed,
> it will be null and scrollable area changed to document.
> 
> |LogicalScroll| finds scrollable area from |MousePressNode|.
> If we save this scrollable area node,
> we can get one more chance to find proper node to scroll.
> 
> 
> Bug: 493078
> Change-Id: I6e81ca0a0d15e0def66c8457840ca9e1343e8dba
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1611620
> Commit-Queue: Lan Wei <lanwei@chromium.org>
> Reviewed-by: Lan Wei <lanwei@chromium.org>
> Reviewed-by: David Bokan <bokan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#663040}

TBR=bokan@chromium.org,lanwei@chromium.org,bluewhale.marc@gmail.com

Change-Id: I4b8ea440dc16022077746d7924506e7f03ac1673
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 493078
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1628880Reviewed-by: Mason Freed <masonfreed@chromium.org>
Commit-Queue: Mason Freed <masonfreed@chromium.org>
Cr-Commit-Position: refs/heads/master@{#663102}

third_party/blink/renderer/core/input/scroll_manager.cc

@@ -94,7 +94,6 @@ void ScrollManager::Trace(blink::Visitor* visitor) {
   visitor->Trace(previous_gesture_scrolled_node_);
   visitor->Trace(scrollbar_handling_scroll_gesture_);
   visitor->Trace(resize_scrollable_area_);
-  visitor->Trace(last_logical_scrolled_node_);
 }
 
 void ScrollManager::ClearGestureScrollState() {
@@ -237,11 +236,6 @@ bool ScrollManager::LogicalScroll(ScrollDirection direction,
   if (!node)
     node = mouse_press_node;
 
-  if ((!node || !node->GetLayoutObject()) &&
-      (last_logical_scrolled_node_ &&
-       last_logical_scrolled_node_->GetLayoutObject()))
-    node = last_logical_scrolled_node_;
-
   if ((!node || !node->GetLayoutObject()) && frame_->View() &&
       frame_->View()->GetLayoutView())
     node = frame_->View()->GetLayoutView()->GetNode();
@@ -325,10 +319,8 @@ bool ScrollManager::LogicalScroll(ScrollDirection direction,
     ScrollResult result = scrollable_area->UserScroll(
         granularity, ToScrollDelta(physical_direction, 1));
 
-    if (result.DidScroll()) {
-      last_logical_scrolled_node_ = scroll_chain_node;
+    if (result.DidScroll())
       return true;
-    }
   }
 
   return false;

third_party/blink/renderer/core/input/scroll_manager.h

@@ -153,8 +153,6 @@ class CORE_EXPORT ScrollManager
 
   Member<Node> scroll_gesture_handling_node_;
 
-  Member<Node> last_logical_scrolled_node_;
-
   bool last_gesture_scroll_over_embedded_content_view_;
 
   // The most recent Node to scroll natively during this scroll

third_party/blink/web_tests/TestExpectations

@@ -2754,7 +2754,6 @@ crbug.com/893490 [ Mac ] external/wpt/css/css-text/white-space/control-chars-09F
 crbug.com/893480 external/wpt/infrastructure/testdriver/actions/elementTiming.html [ Timeout ]
 crbug.com/893480 external/wpt/infrastructure/testdriver/actions/multiDevice.html [ Failure Timeout ]
 crbug.com/893480 external/wpt/infrastructure/testdriver/actions/actionsWithKeyPressed.html [ Failure Timeout ]
-crbug.com/493078 external/wpt/dom/nodes/keyboard-scroll-removed-node.html [ Failure Timeout ]
 
 # Hit a DCHECK
 crbug.com/918664 external/wpt/css/vendor-imports/mozilla/mozilla-central-reftests/sizing/block-size-with-min-or-max-content-table-1a.html [ Failure Pass ]

third_party/blink/web_tests/external/wpt/dom/metadata/dom/nodes/keyboard-scroll-removed-node.html.ini

-[scrollchain.html]
-  expected:
-    if product == "safari": ERROR

third_party/blink/web_tests/external/wpt/dom/nodes/keyboard-scroll-removed-node.html

-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Keyboard scroll removed node</title>
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<script src="/resources/testdriver.js"></script>
-<script src="/resources/testdriver-actions.js"></script>
-<script src="/resources/testdriver-vendor.js"></script>
-<style>
-  ul {
-    width: 30vw;
-    height: 40vh;
-    overflow-y: scroll;
-  }
-  li {
-    width: 95%;
-    height: 10vh;
-    border: 1px solid black;
-  }
-  #target {
-    background-color: grey;
-  }
-</style>
-</head>
-
-<body>
-  <ul id="list">
-    <li>ITEM 1</li>
-    <li>ITEM 2</li>
-    <li id="target">TARGET ITEM 3</li>
-    <li>ITEM 4</li>
-    <li>ITEM 5</li>
-    <li>ITEM 6</li>
-    <li>ITEM 7</li>
-  </ul>
-</body>
-
-<script>
-  async_test(t => {
-    let listElement = document.getElementById("list");
-    let targetElement = document.getElementById("target");
-    let firstScrollTop, secondScrollTop;
-    let ArrowDownKey = "\uE015";
-    let firstActions = new test_driver.Actions()
-      .pointerMove(10, 10, { origin: targetElement })
-      .pointerDown()
-      .pointerUp()
-      .keyDown(ArrowDownKey)
-      .keyUp(ArrowDownKey)
-      .send()
-      .then(() => {
-        firstScrollTop = listElement.scrollTop;
-        targetElement.remove();
-        let secondAction = new test_driver.Actions()
-          .keyDown(ArrowDownKey)
-          .keyUp(ArrowDownKey)
-          .send()
-          .then(() => {
-            secondScrollTop = listElement.scrollTop;
-            assert_greater_than(secondScrollTop, firstScrollTop);
-            t.done();
-          })
-          .catch(t.unreached_func("Actions sequence failed"));
-      })
-      .catch(t.unreached_func("Actions sequence failed"));
-  }, "Keyboard scrolls, after clicked element is removed, continue to affect previous scroller");
-</script>
-
-</html>
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