devtools: Expose content-visibility locked element info.

DevTools exposes info if the node shown is a locked ancestor instead
of the element itself. This patch adds an additional piece of information
that shows if the highlighted element itself locked and as a result
skips its descendants.

The actual string representation of this will be in a separate patch
in the devtools-frontend repo

R=chrishtr@chromium.org

Bug: 1147510
Change-Id: I6c4dcf8f57eebd40b458f74a73d395daf3442c58
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2585144Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Reviewed-by: Andrey Kosyakov <caseq@chromium.org>
Commit-Queue: vmpstr <vmpstr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836255}

third_party/blink/renderer/core/inspector/build.gni

@@ -99,6 +99,7 @@ blink_core_sources_inspector = [
   "main_thread_debugger.h",
   "network_resources_data.cc",
   "network_resources_data.h",
+  "node_content_visibility_state.h",
   "request_debug_header_scope.cc",
   "request_debug_header_scope.h",
   "resolve_node.cc",

third_party/blink/renderer/core/inspector/inspect_tools.cc

@@ -23,6 +23,7 @@
 #include "third_party/blink/renderer/core/html/html_frame_owner_element.h"
 #include "third_party/blink/renderer/core/inspector/inspector_css_agent.h"
 #include "third_party/blink/renderer/core/inspector/inspector_dom_agent.h"
+#include "third_party/blink/renderer/core/inspector/node_content_visibility_state.h"
 #include "third_party/blink/renderer/core/layout/hit_test_location.h"
 #include "third_party/blink/renderer/core/layout/layout_view.h"
 #include "third_party/blink/renderer/core/page/chrome_client.h"
@@ -98,6 +99,38 @@ Node* HoveredNodeForEvent(LocalFrame* frame,
       ignore_pointer_events_none);
 }
 
+bool IsSelfLocked(Node* node) {
+  auto* element = DynamicTo<Element>(node);
+  if (!element)
+    return false;
+
+  auto* context = element->GetDisplayLockContext();
+  if (!context)
+    return false;
+
+  return context->IsLocked();
+}
+
+NodeContentVisibilityState DetermineSelfContentVisibilityState(Node* node) {
+  return IsSelfLocked(node) ? NodeContentVisibilityState::kIsLocked
+                            : NodeContentVisibilityState::kNone;
+}
+
+std::pair<Node*, NodeContentVisibilityState> DetermineContentVisibilityState(
+    Node* node) {
+  DCHECK(node);
+  std::pair<Node*, NodeContentVisibilityState> result;
+  if (auto* locked_ancestor =
+          DisplayLockUtilities::HighestLockedExclusiveAncestor(*node)) {
+    result.first = locked_ancestor;
+    result.second = NodeContentVisibilityState::kIsLockedAncestor;
+  } else {
+    result.first = node;
+    result.second = DetermineSelfContentVisibilityState(node);
+  }
+  return result;
+}
+
 }  // namespace
 
 // SearchingForNodeTool --------------------------------------------------------
@@ -141,7 +174,8 @@ void SearchingForNodeTool::Draw(float scale) {
                              node->GetDocument().GetFrame();
   overlay_->EnsureAXContext(node);
   InspectorHighlight highlight(node, *highlight_config_, contrast_info_,
-                               append_element_info, false, is_locked_ancestor_);
+                               append_element_info, false,
+                               content_visibility_state_);
   if (event_target_node_) {
     highlight.AppendEventTargetQuads(event_target_node_.Get(),
                                      *highlight_config_);
@@ -189,15 +223,8 @@ bool SearchingForNodeTool::HandleMouseMove(const WebMouseEvent& event) {
   if (!node)
     return true;
 
-  // If |node| is in a display locked subtree, highlight the highest locked
-  // element instead.
-  if (Node* locked_ancestor =
-          DisplayLockUtilities::HighestLockedExclusiveAncestor(*node)) {
-    node = locked_ancestor;
-    is_locked_ancestor_ = true;
-  } else {
-    is_locked_ancestor_ = false;
-  }
+  std::tie(node, content_visibility_state_) =
+      DetermineContentVisibilityState(node);
 
   if (auto* frame_owner = DynamicTo<HTMLFrameOwnerElement>(node)) {
     if (!IsA<LocalFrame>(frame_owner->ContentFrame())) {
@@ -309,13 +336,8 @@ NodeHighlightTool::NodeHighlightTool(
     : InspectTool(overlay, frontend),
       selector_list_(selector_list),
       highlight_config_(std::move(highlight_config)) {
-  if (Node* locked_ancestor =
-          DisplayLockUtilities::HighestLockedExclusiveAncestor(*node)) {
-    is_locked_ancestor_ = true;
-    node_ = locked_ancestor;
-  } else {
-    node_ = node;
-  }
+  std::tie(node_, content_visibility_state_) =
+      DetermineContentVisibilityState(node);
   contrast_info_ = FetchContrast(node_);
 }
 
@@ -375,10 +397,12 @@ void NodeHighlightTool::DrawMatchingSelector() {
     // Skip elements in locked subtrees.
     if (DisplayLockUtilities::NearestLockedExclusiveAncestor(*element))
       continue;
+    NodeContentVisibilityState content_visibility_state =
+        DetermineSelfContentVisibilityState(element);
     InspectorHighlight highlight(element, *highlight_config_, contrast_info_,
                                  false /* append_element_info */,
                                  false /* append_distance_info */,
-                                 false /* is_locked_ancestor */);
+                                 content_visibility_state);
     overlay_->EvaluateInOverlay("drawHighlight", highlight.AsProtocolValue());
   }
 }
@@ -395,7 +419,7 @@ NodeHighlightTool::GetNodeInspectorHighlightAsJson(
   overlay_->EnsureAXContext(node_.Get());
   InspectorHighlight highlight(node_.Get(), *highlight_config_, contrast_info_,
                                append_element_info, append_distance_info,
-                               is_locked_ancestor_);
+                               content_visibility_state_);
   return highlight.AsProtocolValue();
 }
 
@@ -479,12 +503,7 @@ SourceOrderTool::SourceOrderTool(
     std::unique_ptr<InspectorSourceOrderConfig> source_order_config)
     : InspectTool(overlay, frontend),
       source_order_config_(std::move(source_order_config)) {
-  if (Node* locked_ancestor =
-          DisplayLockUtilities::HighestLockedExclusiveAncestor(*node)) {
-    node_ = locked_ancestor;
-  } else {
-    node_ = node;
-  }
+  node_ = DetermineContentVisibilityState(node).first;
 }
 
 String SourceOrderTool::GetOverlayName() {
@@ -581,12 +600,7 @@ bool NearbyDistanceTool::HandleMouseMove(const WebMouseEvent& event) {
       return false;
     }
   }
-
-  // If |node| is in a display locked subtree, highlight the highest locked
-  // element instead.
-  if (Node* locked_ancestor =
-          DisplayLockUtilities::HighestLockedExclusiveAncestor(*node))
-    node = locked_ancestor;
+  node = DetermineContentVisibilityState(node).first;
 
   // Store values for the highlight.
   hovered_node_ = node;
@@ -602,10 +616,11 @@ void NearbyDistanceTool::Draw(float scale) {
   if (!node)
     return;
   overlay_->EnsureAXContext(node);
+  auto content_visibility_state = DetermineSelfContentVisibilityState(node);
   InspectorHighlight highlight(
       node, InspectorHighlight::DefaultConfig(),
       InspectorHighlightContrastInfo(), false /* append_element_info */,
-      true /* append_distance_info */, false /* is_locked_ancestor */);
+      true /* append_distance_info */, content_visibility_state);
   overlay_->EvaluateInOverlay("drawDistances", highlight.AsProtocolValue());
 }
 

third_party/blink/renderer/core/inspector/inspect_tools.h

@@ -6,9 +6,11 @@
 #define THIRD_PARTY_BLINK_RENDERER_CORE_INSPECTOR_INSPECT_TOOLS_H_
 
 #include <vector>
+
 #include <v8-inspector.h>
 #include "base/macros.h"
 #include "third_party/blink/renderer/core/inspector/inspector_overlay_agent.h"
+#include "third_party/blink/renderer/core/inspector/node_content_visibility_state.h"
 
 namespace blink {
 
@@ -42,7 +44,10 @@ class SearchingForNodeTool : public InspectTool {
 
   Member<InspectorDOMAgent> dom_agent_;
   bool ua_shadow_;
-  bool is_locked_ancestor_ = false;
+
+  NodeContentVisibilityState content_visibility_state_ =
+      NodeContentVisibilityState::kNone;
+
   Member<Node> hovered_node_;
   Member<Node> event_target_node_;
   std::unique_ptr<InspectorHighlightConfig> highlight_config_;
@@ -97,7 +102,8 @@ class NodeHighlightTool : public InspectTool {
   void Trace(Visitor* visitor) const override;
   String GetOverlayName() override;
 
-  bool is_locked_ancestor_ = false;
+  NodeContentVisibilityState content_visibility_state_ =
+      NodeContentVisibilityState::kNone;
   Member<Node> node_;
   String selector_list_;
   std::unique_ptr<InspectorHighlightConfig> highlight_config_;

third_party/blink/renderer/core/inspector/inspector_highlight.cc

@@ -20,6 +20,7 @@
 #include "third_party/blink/renderer/core/geometry/dom_rect.h"
 #include "third_party/blink/renderer/core/inspector/dom_traversal_utils.h"
 #include "third_party/blink/renderer/core/inspector/inspector_dom_agent.h"
+#include "third_party/blink/renderer/core/inspector/node_content_visibility_state.h"
 #include "third_party/blink/renderer/core/inspector/protocol/Overlay.h"
 #include "third_party/blink/renderer/core/layout/adjust_for_absolute_zoom.h"
 #include "third_party/blink/renderer/core/layout/geometry/physical_offset.h"
@@ -1465,7 +1466,7 @@ InspectorHighlight::InspectorHighlight(
     const InspectorHighlightContrastInfo& node_contrast,
     bool append_element_info,
     bool append_distance_info,
-    bool is_locked_ancestor)
+    NodeContentVisibilityState content_visibility_state)
     : InspectorHighlightBase(node),
       show_rulers_(highlight_config.show_rulers),
       show_extension_lines_(highlight_config.show_extension_lines),
@@ -1484,12 +1485,22 @@ InspectorHighlight::InspectorHighlight(
                     highlight_config.contrast_algorithm);
   }
 
-  if (element_info_ && is_locked_ancestor)
-    element_info_->setString("isLockedAncestor", "true");
   if (element_info_) {
+    switch (content_visibility_state) {
+      case NodeContentVisibilityState::kNone:
+        break;
+      case NodeContentVisibilityState::kIsLocked:
+        element_info_->setBoolean("isLocked", true);
+        break;
+      case NodeContentVisibilityState::kIsLockedAncestor:
+        element_info_->setBoolean("isLockedAncestor", true);
+        break;
+    }
+
     element_info_->setBoolean("showAccessibilityInfo",
                               show_accessibility_info_);
   }
+
   if (append_distance_info)
     AppendDistanceInfo(node);
 }

third_party/blink/renderer/core/inspector/inspector_highlight.h

@@ -7,6 +7,7 @@
 
 #include "third_party/blink/renderer/core/core_export.h"
 #include "third_party/blink/renderer/core/dom/pseudo_element.h"
+#include "third_party/blink/renderer/core/inspector/node_content_visibility_state.h"
 #include "third_party/blink/renderer/core/inspector/protocol/DOM.h"
 #include "third_party/blink/renderer/platform/geometry/float_quad.h"
 #include "third_party/blink/renderer/platform/geometry/layout_rect.h"
@@ -185,7 +186,7 @@ class CORE_EXPORT InspectorHighlight : public InspectorHighlightBase {
                      const InspectorHighlightContrastInfo&,
                      bool append_element_info,
                      bool append_distance_info,
-                     bool is_locked_ancestor);
+                     NodeContentVisibilityState content_visibility_state);
   explicit InspectorHighlight(float scale);
   ~InspectorHighlight();
 

third_party/blink/renderer/core/inspector/node_content_visibility_state.h

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_INSPECTOR_NODE_CONTENT_VISIBILITY_STATE_H_
+#define THIRD_PARTY_BLINK_RENDERER_CORE_INSPECTOR_NODE_CONTENT_VISIBILITY_STATE_H_
+
+// The state of content visibility:
+//  - kNone means that the node has no content-visibility interactions
+//  - kIsLocked means that the node is itself locked and is skipping its
+//    contents. However, the node is not in a subtree of a locked element.
+//  - kIsLockedAncestor means that the initial node was in a locked subtree
+//    so we instead are showing this ancestor.
+enum class NodeContentVisibilityState { kNone, kIsLocked, kIsLockedAncestor };
+
+#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_INSPECTOR_NODE_CONTENT_VISIBILITY_STATE_H_

third_party/blink/web_tests/http/tests/devtools/elements/highlight/highlight-display-locked-expected.txt

@@ -93,6 +93,7 @@ container{
     "accessibleName": "",
     "accessibleRole": "generic",
     "layoutObjectName": "LayoutNGBlockFlow",
+    "isLocked": true,
     "showAccessibilityInfo": true
   }
 }
@@ -189,7 +190,7 @@ child{
     "accessibleName": "",
     "accessibleRole": "generic",
     "layoutObjectName": "LayoutNGBlockFlow",
-    "isLockedAncestor": "true",
+    "isLockedAncestor": true,
     "showAccessibilityInfo": true
   }
 }

third_party/blink/web_tests/http/tests/devtools/elements/highlight/highlight-display-locked-grid-expected.txt

@@ -93,6 +93,7 @@ container{
     "accessibleName": "",
     "accessibleRole": "generic",
     "layoutObjectName": "LayoutGrid",
+    "isLocked": true,
     "showAccessibilityInfo": true
   }
 }
@@ -189,7 +190,7 @@ child{
     "accessibleName": "",
     "accessibleRole": "generic",
     "layoutObjectName": "LayoutGrid",
-    "isLockedAncestor": "true",
+    "isLockedAncestor": true,
     "showAccessibilityInfo": true
   }
 }

third_party/blink/web_tests/http/tests/devtools/elements/highlight/highlight-display-locked-in-frame-expected.txt

@@ -93,6 +93,7 @@ container{
     "accessibleName": "",
     "accessibleRole": "",
     "layoutObjectName": "LayoutIFrame",
+    "isLocked": true,
     "showAccessibilityInfo": true
   }
 }
@@ -189,7 +190,7 @@ child{
     "accessibleName": "",
     "accessibleRole": "",
     "layoutObjectName": "LayoutIFrame",
-    "isLockedAncestor": "true",
+    "isLockedAncestor": true,
     "showAccessibilityInfo": true
   }
 }