Make style & layout containment create a clip-related property

As of https://crrev.com/619964, style & layout containment creates
an isolation boundary which means clip-related subtree updates can be
skipped. PaintLayer::ClippingContainer is used for the clip property
tree state of a squashing layer. This clipping container could be an
ancestor of a style & layout isolation boundary. If a clip changed on
a clipping container ancestor of an isolation boundary, the clip node of
squashing layers below could become stale. This patch ensures
PaintLayer::ClippingContainer stops at style & layout containment
boundaries by making style & layout containment a clip-related property.

Bug: 1044895
Change-Id: I898df21c0f65f79114564938042356b7ef587c19
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2025313
Commit-Queue: Philip Rogers <pdr@chromium.org>
Reviewed-by: vmpstr <vmpstr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#736142}

third_party/blink/renderer/core/display_lock/display_lock_context_test.cc

@@ -1515,6 +1515,7 @@ TEST_F(DisplayLockContextTest,
       width: 100px;
       height: 100px;
       contain: style layout;
+      will-change: transform;
     }
     #composited {
       will-change: transform;

third_party/blink/renderer/core/layout/layout_object.cc

@@ -470,20 +470,26 @@ LayoutObject* LayoutObject::NextInPreOrder() const {
 }
 
 bool LayoutObject::HasClipRelatedProperty() const {
-  // TODO(trchen): Refactor / remove this function.
   // This function detects a bunch of properties that can potentially affect
-  // clip inheritance chain. However such generalization is practially useless
+  // clip inheritance chain. However such generalization is practically useless
   // because these properties change clip inheritance in different way that
   // needs to be handled explicitly.
   // CSS clip applies clip to the current element and all descendants.
-  // CSS overflow clip applies only to containg-block descendants.
+  // CSS overflow clip applies only to containing-block descendants.
   // CSS contain:paint applies to all descendants by making itself a containing
   // block for all descendants.
   // CSS clip-path/mask/filter induces a stacking context and applies inherited
   // clip to that stacking context, while resetting clip for descendants. This
   // special behavior is already handled elsewhere.
-  if (HasClip() || HasOverflowClip() || ShouldApplyPaintContainment())
+  if (HasClip() || HasOverflowClip())
     return true;
+  // Paint containment establishes isolation which creates clip isolation nodes.
+  // Style & Layout containment also establish isolation (see
+  // |NeedsIsolationNodes| in PaintPropertyTreeBuilder).
+  if (ShouldApplyPaintContainment() ||
+      (ShouldApplyStyleContainment() && ShouldApplyLayoutContainment())) {
+    return true;
+  }
   if (IsBox() && ToLayoutBox(this)->HasControlClip())
     return true;
   return false;

third_party/blink/renderer/core/paint/compositing/composited_layer_mapping_test.cc

@@ -1803,4 +1803,52 @@ TEST_F(CompositedLayerMappingTest,
   EXPECT_TRUE(mapping->NeedsRepaint(*vertical_scrollbar_layer));
 }
 
+TEST_F(CompositedLayerMappingTest, IsolationClippingContainer) {
+  SetBodyInnerHTML(R"HTML(
+    <style>
+      #hideable {
+        overflow: hidden;
+        height: 10px;
+      }
+      .isolation {
+        contain: style layout;
+        height: 100px;
+      }
+      .squash-container {
+        will-change: transform;
+      }
+      .squashed {
+        position: absolute;
+        top: 0;
+        left: 0;
+        width: 100px;
+        height: 100px;
+      }
+    </style>
+    <div id="hideable">
+      <div class="isolation" id="isolation_a">
+        <div class="squash-container" id="squash_container_a">a</div>
+        <div class="squashed"></div>
+      </div>
+      <div class="isolation">
+        <div class="squash-container">b</div>
+        <div class="squashed"></div>
+      </div>
+    </div>
+  )HTML");
+
+  Element* hideable = GetDocument().getElementById("hideable");
+  hideable->SetInlineStyleProperty(CSSPropertyID::kOverflow, "visible");
+
+  UpdateAllLifecyclePhasesForTest();
+
+  auto* isolation_a = GetDocument().getElementById("isolation_a");
+  auto* isolation_a_object = isolation_a->GetLayoutObject();
+
+  auto* squash_container_a = GetDocument().getElementById("squash_container_a");
+  PaintLayer* squash_container_a_layer =
+      ToLayoutBoxModelObject(squash_container_a->GetLayoutObject())->Layer();
+  EXPECT_EQ(squash_container_a_layer->ClippingContainer(), isolation_a_object);
+}
+
 }  // namespace blink