[SH-Blink] Create TextFragmentSelectorGenerator with page.

Create TextFragmentSelectorGenerator with page and set selection
information when context menu is shown.
This is done so that Java code can just call the GenerateSelector
function without any arguments and generation can happen for the latest
selected text.

Follow-up CL
https://chromium-review.googlesource.com/c/chromium/src/+/2341662
will connect to browser-side component.

Bug: 1102382
Change-Id: I5574f5b40e5a74bef56698e2de5a9b1fea17e0d0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2340734Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: David Bokan <bokan@chromium.org>
Commit-Queue: Gayane Petrosyan <gayane@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797256}

third_party/blink/renderer/core/page/context_menu_controller.cc

@@ -41,6 +41,7 @@
 #include "third_party/blink/renderer/core/dom/node.h"
 #include "third_party/blink/renderer/core/editing/editing_tri_state.h"
 #include "third_party/blink/renderer/core/editing/editor.h"
+#include "third_party/blink/renderer/core/editing/ephemeral_range.h"
 #include "third_party/blink/renderer/core/editing/frame_selection.h"
 #include "third_party/blink/renderer/core/editing/ime/input_method_controller.h"
 #include "third_party/blink/renderer/core/editing/selection_controller.h"
@@ -69,6 +70,7 @@
 #include "third_party/blink/renderer/core/page/context_menu_provider.h"
 #include "third_party/blink/renderer/core/page/focus_controller.h"
 #include "third_party/blink/renderer/core/page/page.h"
+#include "third_party/blink/renderer/core/page/scrolling/text_fragment_selector_generator.h"
 #include "third_party/blink/renderer/platform/exported/wrapped_resource_response.h"
 
 namespace blink {
@@ -246,6 +248,17 @@ bool ContextMenuController::ShowContextMenu(LocalFrame* frame,
             PhysicalOffset(FlooredIntPoint(point)));
   }
 
+  // Store text selection when it happens as it might be cleared when the
+  // browser will request |TextFragmentSelectorGenerator| to generator selector.
+  if (!selected_frame->Selection().SelectedText().IsEmpty()) {
+    VisibleSelectionInFlatTree selection =
+        selected_frame->Selection().ComputeVisibleSelectionInFlatTree();
+    EphemeralRangeInFlatTree selection_range(selection.Start(),
+                                             selection.End());
+    page_->GetTextFragmentSelectorGenerator().UpdateSelection(selected_frame,
+                                                              selection_range);
+  }
+
   WebContextMenuData data;
   data.mouse_position = selected_frame->View()->FrameToViewport(
       result.RoundedPointInInnerNodeFrame());

third_party/blink/renderer/core/page/page.cc

@@ -75,6 +75,7 @@
 #include "third_party/blink/renderer/core/page/scoped_page_pauser.h"
 #include "third_party/blink/renderer/core/page/scrolling/overscroll_controller.h"
 #include "third_party/blink/renderer/core/page/scrolling/scrolling_coordinator.h"
+#include "third_party/blink/renderer/core/page/scrolling/text_fragment_selector_generator.h"
 #include "third_party/blink/renderer/core/page/scrolling/top_document_root_scroller_controller.h"
 #include "third_party/blink/renderer/core/page/spatial_navigation_controller.h"
 #include "third_party/blink/renderer/core/page/validation_message_client_impl.h"
@@ -225,7 +226,9 @@ Page::Page(PageClients& page_clients)
       next_related_page_(this),
       prev_related_page_(this),
       autoplay_flags_(0),
-      web_text_autosizer_page_info_({0, 0, 1.f}) {
+      web_text_autosizer_page_info_({0, 0, 1.f}),
+      text_fragment_selector_generator_(
+          MakeGarbageCollected<TextFragmentSelectorGenerator>()) {
   DCHECK(!AllPages().Contains(this));
   AllPages().insert(this);
 
@@ -914,6 +917,7 @@ void Page::Trace(Visitor* visitor) const {
   visitor->Trace(plugins_changed_observers_);
   visitor->Trace(next_related_page_);
   visitor->Trace(prev_related_page_);
+  visitor->Trace(text_fragment_selector_generator_);
   Supplementable<Page>::Trace(visitor);
 }
 

third_party/blink/renderer/core/page/page.h

@@ -75,6 +75,7 @@ class PageScaleConstraintsSet;
 class PluginData;
 class PluginsChangedObserver;
 class PointerLockController;
+class TextFragmentSelectorGenerator;
 class ScopedPagePauser;
 class ScrollingCoordinator;
 class ScrollbarTheme;
@@ -356,6 +357,10 @@ class CORE_EXPORT Page final : public GarbageCollected<Page>,
 
   static void PrepareForLeakDetection();
 
+  TextFragmentSelectorGenerator& GetTextFragmentSelectorGenerator() const {
+    return *text_fragment_selector_generator_;
+  }
+
  private:
   friend class ScopedPagePauser;
 
@@ -477,6 +482,8 @@ class CORE_EXPORT Page final : public GarbageCollected<Page>,
 
   WebScopedVirtualTimePauser history_navigation_virtual_time_pauser_;
 
+  const Member<TextFragmentSelectorGenerator> text_fragment_selector_generator_;
+
   DISALLOW_COPY_AND_ASSIGN(Page);
 };
 

third_party/blink/renderer/core/page/scrolling/text_fragment_selector_generator.cc

@@ -15,27 +15,31 @@ namespace blink {
 constexpr int kExactTextMaxChars = 300;
 constexpr int kNoContextMinChars = 20;
 
-TextFragmentSelectorGenerator::TextFragmentSelectorGenerator(
-    LocalFrame* frame,
-    base::OnceCallback<void(const TextFragmentSelector&)> callback)
-    : frame_(frame), callback_(std::move(callback)) {}
-
-// TextFragmentSelectorGenerator is responsible for generating text fragment
-// selectors that have a unique match.
-void TextFragmentSelectorGenerator::GenerateSelector(
+void TextFragmentSelectorGenerator::UpdateSelection(
+    LocalFrame* selection_frame,
     const EphemeralRangeInFlatTree& selection_range) {
+  selection_frame_ = selection_frame;
+  selection_range_ = MakeGarbageCollected<Range>(
+      selection_range.GetDocument(),
+      ToPositionInDOMTree(selection_range.StartPosition()),
+      ToPositionInDOMTree(selection_range.EndPosition()));
+}
+
+void TextFragmentSelectorGenerator::GenerateSelector() {
+  EphemeralRangeInFlatTree ephemeral_range(selection_range_);
+
   const TextFragmentSelector kInvalidSelector(
       TextFragmentSelector::SelectorType::kInvalid);
 
   Node& start_first_block_ancestor =
       FindBuffer::GetFirstBlockLevelAncestorInclusive(
-          *selection_range.StartPosition().AnchorNode());
+          *ephemeral_range.StartPosition().AnchorNode());
   Node& end_first_block_ancestor =
       FindBuffer::GetFirstBlockLevelAncestorInclusive(
-          *selection_range.EndPosition().AnchorNode());
+          *ephemeral_range.EndPosition().AnchorNode());
 
   if (!start_first_block_ancestor.isSameNode(&end_first_block_ancestor))
-    std::move(callback_).Run(kInvalidSelector);
+    NotifySelectorReady(kInvalidSelector);
 
   // TODO(gayane): If same node, need to check if start and end are interrupted
   // by a block. Example: <div>start of the selection <div> sub block </div>end
@@ -43,16 +47,16 @@ void TextFragmentSelectorGenerator::GenerateSelector(
 
   // TODO(gayane): Move selection start and end to contain full words.
 
-  String selected_text = PlainText(selection_range);
+  String selected_text = PlainText(ephemeral_range);
 
   if (selected_text.length() < kNoContextMinChars ||
       selected_text.length() > kExactTextMaxChars)
-    std::move(callback_).Run(kInvalidSelector);
+    NotifySelectorReady(kInvalidSelector);
 
   selector_ = std::make_unique<TextFragmentSelector>(
       TextFragmentSelector::SelectorType::kExact, selected_text, "", "", "");
   TextFragmentFinder finder(*this, *selector_);
-  finder.FindMatch(*frame_->GetDocument());
+  finder.FindMatch(*selection_frame_->GetDocument());
 }
 
 void TextFragmentSelectorGenerator::DidFindMatch(
@@ -60,16 +64,28 @@ void TextFragmentSelectorGenerator::DidFindMatch(
     const TextFragmentAnchorMetrics::Match match_metrics,
     bool is_unique) {
   if (is_unique) {
-    std::move(callback_).Run(*selector_);
+    NotifySelectorReady(*selector_);
   } else {
     // TODO(gayane): Should add more range and/or context.
-    std::move(callback_).Run(
+    NotifySelectorReady(
         TextFragmentSelector(TextFragmentSelector::SelectorType::kInvalid));
   }
 }
 
+void TextFragmentSelectorGenerator::SetCallbackForTesting(
+    base::OnceCallback<void(const TextFragmentSelector&)> callback) {
+  callback_for_tests_ = std::move(callback);
+}
+
+void TextFragmentSelectorGenerator::NotifySelectorReady(
+    const TextFragmentSelector& selector) {
+  if (!callback_for_tests_.is_null())
+    std::move(callback_for_tests_).Run(selector);
+}
+
 void TextFragmentSelectorGenerator::Trace(Visitor* visitor) const {
-  visitor->Trace(frame_);
+  visitor->Trace(selection_frame_);
+  visitor->Trace(selection_range_);
 }
 
 }  // namespace blink

third_party/blink/renderer/core/page/scrolling/text_fragment_selector_generator.h

@@ -13,28 +13,46 @@ namespace blink {
 
 class LocalFrame;
 
+// TextFragmentSelectorGenerator is responsible for generating text fragment
+// selectors for the user selected text according to spec in
+// https://github.com/WICG/scroll-to-text-fragment#proposed-solution.
+// Generated selectors would be later used to highlight the same
+// text if successfully parsed by |TextFragmentAnchor |. Generation will be
+// triggered when users request "link to text" for the selected text.
 class CORE_EXPORT TextFragmentSelectorGenerator final
     : public GarbageCollected<TextFragmentSelectorGenerator>,
       public TextFragmentFinder::Client {
  public:
-  TextFragmentSelectorGenerator(
-      LocalFrame* frame,
-      base::OnceCallback<void(const TextFragmentSelector&)> callback);
+  explicit TextFragmentSelectorGenerator() = default;
+
+  // Sets the frame and range of the current selection.
+  void UpdateSelection(LocalFrame* selection_frame,
+                       const EphemeralRangeInFlatTree& selection_range);
 
-  void GenerateSelector(const EphemeralRangeInFlatTree& selection_range);
+  // Generates selector for current selection.
+  void GenerateSelector();
 
   // TextFragmentFinder::Client interface
   void DidFindMatch(const EphemeralRangeInFlatTree& match,
                     const TextFragmentAnchorMetrics::Match match_metrics,
                     bool is_unique) override;
 
+  // Sets the callback used for notifying test results of |GenerateSelector|.
+  void SetCallbackForTesting(
+      base::OnceCallback<void(const TextFragmentSelector&)> callback);
+
+  // Notifies the results of |GenerateSelector|.
+  void NotifySelectorReady(const TextFragmentSelector& selector);
+
   void Trace(Visitor*) const;
 
  private:
-  Member<LocalFrame> frame_;
-  base::OnceCallback<void(const TextFragmentSelector&)> callback_;
+  Member<LocalFrame> selection_frame_;
+  Member<Range> selection_range_;
   std::unique_ptr<TextFragmentSelector> selector_;
 
+  base::OnceCallback<void(const TextFragmentSelector&)> callback_for_tests_;
+
   DISALLOW_COPY_AND_ASSIGN(TextFragmentSelectorGenerator);
 };
 

third_party/blink/renderer/core/page/scrolling/text_fragment_selector_generator_test.cc

@@ -41,10 +41,13 @@ TEST_F(TextFragmentSelectorGeneratorTest, ExactTextSelector) {
         callback_called = true;
       });
 
-  TextFragmentSelectorGenerator generator(GetDocument().GetFrame(),
-                                          std::move(callback));
-  generator.GenerateSelector(
+  TextFragmentSelectorGenerator generator;
+  generator.UpdateSelection(
+      GetDocument().GetFrame(),
       ToEphemeralRangeInFlatTree(EphemeralRange(selected_start, selected_end)));
+  generator.SetCallbackForTesting(std::move(callback));
+  generator.GenerateSelector();
+
   EXPECT_TRUE(callback_called);
 }
 
@@ -69,10 +72,13 @@ TEST_F(TextFragmentSelectorGeneratorTest, ExactTextWithNestedTextNodes) {
         callback_called = true;
       });
 
-  TextFragmentSelectorGenerator generator(GetDocument().GetFrame(),
-                                          std::move(callback));
-  generator.GenerateSelector(
+  TextFragmentSelectorGenerator generator;
+  generator.UpdateSelection(
+      GetDocument().GetFrame(),
       ToEphemeralRangeInFlatTree(EphemeralRange(selected_start, selected_end)));
+  generator.SetCallbackForTesting(std::move(callback));
+  generator.GenerateSelector();
+
   EXPECT_TRUE(callback_called);
 }
 
@@ -96,10 +102,13 @@ TEST_F(TextFragmentSelectorGeneratorTest, ExactTextWithExtraSpace) {
         callback_called = true;
       });
 
-  TextFragmentSelectorGenerator generator(GetDocument().GetFrame(),
-                                          std::move(callback));
-  generator.GenerateSelector(
+  TextFragmentSelectorGenerator generator;
+  generator.UpdateSelection(
+      GetDocument().GetFrame(),
       ToEphemeralRangeInFlatTree(EphemeralRange(selected_start, selected_end)));
+  generator.SetCallbackForTesting(std::move(callback));
+  generator.GenerateSelector();
+
   EXPECT_TRUE(callback_called);
 }
 
@@ -125,10 +134,13 @@ TEST_F(TextFragmentSelectorGeneratorTest, MultiblockSelection) {
         callback_called = true;
       });
 
-  TextFragmentSelectorGenerator generator(GetDocument().GetFrame(),
-                                          std::move(callback));
-  generator.GenerateSelector(
+  TextFragmentSelectorGenerator generator;
+  generator.UpdateSelection(
+      GetDocument().GetFrame(),
       ToEphemeralRangeInFlatTree(EphemeralRange(selected_start, selected_end)));
+  generator.SetCallbackForTesting(std::move(callback));
+  generator.GenerateSelector();
+
   EXPECT_TRUE(callback_called);
 }