Highlight active match after scrolling for find-in-page

When using beforematch to expand a content-visibility: hidden-matchable
element asynchronously with an animation, the active match usually
doesn't get highlighted.
This patch makes sure highlighting happens after the scroll, fixing the
issue.

Bug: 1114208
Change-Id: I8dc60aa39461e05d43f94a863514a261e19e4e8a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2342577Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Reviewed-by: vmpstr <vmpstr@chromium.org>
Commit-Queue: Joey Arhar <jarhar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797000}

third_party/blink/renderer/core/display_lock/display_lock_document_state.h

@@ -54,7 +54,7 @@ class CORE_EXPORT DisplayLockDocumentState final
   // Returns true if all activatable locks have been forced.
   bool ActivatableDisplayLocksForced() const;
 
-  class ScopedForceActivatableDisplayLocks {
+  class CORE_EXPORT ScopedForceActivatableDisplayLocks {
     STACK_ALLOCATED();
 
    public:

third_party/blink/renderer/core/editing/finder/text_finder.cc

@@ -442,10 +442,17 @@ void TextFinder::DidFindMatch(int identifier,
           active_match_index_ + 1, identifier);
     }
   }
-  OwnerFrame().GetFrame()->GetDocument()->Markers().AddTextMatchMarker(
-      EphemeralRange(result_range),
-      found_active_match ? TextMatchMarker::MatchStatus::kActive
-                         : TextMatchMarker::MatchStatus::kInactive);
+  DocumentMarkerController& marker_controller =
+      OwnerFrame().GetFrame()->GetDocument()->Markers();
+  EphemeralRange ephemeral_result_range(result_range);
+  // Scroll() may have added a match marker to this range already.
+  if (!marker_controller.FirstMarkerIntersectingEphemeralRange(
+          ephemeral_result_range, DocumentMarker::MarkerTypes::TextMatch())) {
+    marker_controller.AddTextMatchMarker(
+        EphemeralRange(result_range),
+        found_active_match ? TextMatchMarker::MatchStatus::kActive
+                           : TextMatchMarker::MatchStatus::kInactive);
+  }
 
   find_matches_cache_.push_back(FindMatch(result_range, current_total_matches));
 }
@@ -825,6 +832,21 @@ void TextFinder::Scroll(std::unique_ptr<AsyncScrollContext> context) {
         OwnerFrame().GetFrameView()->ConvertToRootFrame(
             ComputeTextRect(EphemeralRange(context->range))));
   }
+
+  // DidFindMatch will race against this to add a text match marker to this
+  // range. In the case where the match is hidden and the beforematch event (or
+  // anything else) reveals the range in between DidFindMatch and this function,
+  // we need to add the marker again or else it won't show up at all.
+  EphemeralRange ephemeral_range(context->range);
+  DocumentMarkerController& marker_controller =
+      OwnerFrame().GetFrame()->GetDocument()->Markers();
+  if (!context->options.run_synchronously_for_testing &&
+      !marker_controller.FirstMarkerIntersectingEphemeralRange(
+          ephemeral_range, DocumentMarker::MarkerTypes::TextMatch())) {
+    marker_controller.AddTextMatchMarker(ephemeral_range,
+                                         TextMatchMarker::MatchStatus::kActive);
+    SetMarkerActive(context->range, true);
+  }
 }
 
 }  // namespace blink

third_party/blink/renderer/core/editing/finder/text_finder_test.cc

@@ -11,12 +11,15 @@
 #include "third_party/blink/public/web/web_document.h"
 #include "third_party/blink/renderer/bindings/core/v8/script_source_code.h"
 #include "third_party/blink/renderer/bindings/core/v8/v8_binding_for_testing.h"
+#include "third_party/blink/renderer/core/display_lock/display_lock_document_state.h"
 #include "third_party/blink/renderer/core/dom/document.h"
 #include "third_party/blink/renderer/core/dom/node_list.h"
 #include "third_party/blink/renderer/core/dom/range.h"
 #include "third_party/blink/renderer/core/dom/shadow_root.h"
 #include "third_party/blink/renderer/core/editing/ephemeral_range.h"
 #include "third_party/blink/renderer/core/editing/finder/find_in_page_coordinates.h"
+#include "third_party/blink/renderer/core/editing/markers/document_marker.h"
+#include "third_party/blink/renderer/core/editing/markers/document_marker_controller.h"
 #include "third_party/blink/renderer/core/frame/frame_test_helpers.h"
 #include "third_party/blink/renderer/core/frame/local_frame_view.h"
 #include "third_party/blink/renderer/core/frame/visual_viewport.h"
@@ -25,6 +28,8 @@
 #include "third_party/blink/renderer/core/layout/text_autosizer.h"
 #include "third_party/blink/renderer/core/page/page.h"
 #include "third_party/blink/renderer/core/script/classic_script.h"
+#include "third_party/blink/renderer/core/testing/sim/sim_request.h"
+#include "third_party/blink/renderer/core/testing/sim/sim_test.h"
 #include "third_party/blink/renderer/platform/bindings/exception_state.h"
 #include "third_party/blink/renderer/platform/testing/testing_platform_support.h"
 #include "third_party/blink/renderer/platform/testing/unit_test_helpers.h"
@@ -61,6 +66,14 @@ class TextFinderTest : public testing::Test {
   Persistent<TextFinder> text_finder_;
 };
 
+class TextFinderSimTest : public SimTest {
+ public:
+  TextFinder& GetTextFinder() {
+    return WebLocalFrameImpl::FromFrame(GetDocument().GetFrame())
+        ->EnsureTextFinder();
+  }
+};
+
 v8::Local<v8::Value> TextFinderTest::EvalJs(const std::string& script) {
   return ClassicScript::CreateUnspecifiedScript(
              ScriptSourceCode(script.c_str()))
@@ -715,6 +728,47 @@ TEST_F(TextFinderTest, BeforeMatchEventRemoveElement) {
 // TODO(jarhar): Write more tests here once we decide on a behavior here:
 // https://github.com/WICG/display-locking/issues/150
 
+TEST_F(TextFinderSimTest, BeforeMatchEventAsyncExpandHighlight) {
+  SimRequest request("https://example.com/test.html", "text/html");
+  LoadURL("https://example.com/test.html");
+  request.Complete(R"HTML(
+    <!DOCTYPE html>
+    <style>
+      .hidden {
+        content-visibility: hidden-matchable;
+      }
+    </style>
+
+    <div id=hiddenid class=hidden>hidden</div>
+
+    <script>
+      hiddenid.addEventListener('beforematch', () => {
+        setTimeout(() => {
+          hiddenid.classList.remove('hidden');
+        }, 0);
+      });
+    </script>
+  )HTML");
+  Compositor().BeginFrame();
+
+  auto forced_activatable_locks = GetDocument()
+                                      .GetDisplayLockDocumentState()
+                                      .GetScopedForceActivatableLocks();
+  GetDocument().UpdateStyleAndLayout(DocumentUpdateReason::kFindInPage);
+  GetTextFinder().Find(/*identifier=*/0, WebString(String("hidden")),
+                       *mojom::blink::FindOptions::New(),
+                       /*wrap_within_frame=*/false);
+
+  Compositor().BeginFrame();
+  Compositor().BeginFrame();
+
+  HeapVector<Member<DocumentMarker>> markers =
+      GetDocument().Markers().Markers();
+  ASSERT_EQ(markers.size(), 1u);
+  DocumentMarker* marker = markers[0];
+  EXPECT_TRUE(marker->GetType() == DocumentMarker::kTextMatch);
+}
+
 TEST_F(TextFinderTest, FindTextAcrossCommentNode) {
   GetDocument().body()->setInnerHTML(
       "<span>abc</span><!--comment--><span>def</span>");