Gracefully handle duplicated entries in PictureLayerImpl::SetPaintWor…

…kletInputs()

Clear the cached entry to nullopt so that the next duplicated
entry will get a nullopt instead of an invalid PaintRecord.

(cherry picked from commit 5c80767)

Bug: 1442690
Change-Id: Id5089f36820d9deffba464f2b18594fb86123528
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4570147
Reviewed-by: Justin Novosad <junov@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#1150362}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4583309
Auto-Submit: Xianzhu Wang <wangxianzhu@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/branch-heads/5790@{#250}
Cr-Branched-From: 1d71a33-refs/heads/main@{#1148114}

cc/layers/picture_layer_impl.cc

@@ -2114,6 +2114,9 @@ void PictureLayerImpl::SetPaintWorkletInputs(
     // Attempt to re-use an existing PaintRecord if possible.
     new_records[input] = std::make_pair(
         paint_image_id, std::move(paint_worklet_records_[input].second));
+    // The move constructor of absl::optional does not clear the source to
+    // nullopt.
+    paint_worklet_records_[input].second = absl::nullopt;
   }
   paint_worklet_records_.swap(new_records);
 

cc/layers/picture_layer_impl_unittest.cc

@@ -6260,6 +6260,37 @@ TEST_F(LegacySWPictureLayerImplTest, PaintWorkletInputs) {
   EXPECT_TRUE(pending_layer()->GetPaintWorkletRecordMap().contains(input3));
 }
 
+TEST_F(LegacySWPictureLayerImplTest, PaintWorkletInputsIdenticalEntries) {
+  gfx::Size layer_bounds(1000, 1000);
+
+  auto recording_source = FakeRecordingSource::CreateRecordingSource(
+      gfx::Rect(layer_bounds), layer_bounds);
+  scoped_refptr<TestPaintWorkletInput> input =
+      base::MakeRefCounted<TestPaintWorkletInput>(gfx::SizeF(100, 100));
+  PaintImage image = CreatePaintWorkletPaintImage(input);
+  recording_source->add_draw_image(image, gfx::Point(100, 100));
+  recording_source->add_draw_image(image, gfx::Point(100, 100));
+  recording_source->Rerecord();
+
+  // All inputs should be registered on the pending layer.
+  SetupPendingTree(recording_source->CreateRasterSource(), gfx::Size(),
+                   Region(gfx::Rect(layer_bounds)));
+  EXPECT_EQ(pending_layer()->GetPaintWorkletRecordMap().size(), 1u);
+  EXPECT_TRUE(pending_layer()->GetPaintWorkletRecordMap().contains(input));
+
+  PaintRecord record;
+  pending_layer()->SetPaintWorkletRecord(input, record);
+  pending_layer()->picture_layer_tiling_set()->RemoveAllTiles();
+  recording_source->Rerecord();
+  pending_layer()->SetRasterSource(recording_source->CreateRasterSource(),
+                                   Region());
+  EXPECT_EQ(pending_layer()->GetPaintWorkletRecordMap().size(), 1u);
+  auto it = pending_layer()->GetPaintWorkletRecordMap().find(input);
+  ASSERT_NE(it, pending_layer()->GetPaintWorkletRecordMap().end());
+  // For now the paint record is cleared for multiple identical inputs.
+  EXPECT_FALSE(it->second.second.has_value());
+}
+
 TEST_F(LegacySWPictureLayerImplTest, NoTilingsUsesScaleOne) {
   auto render_pass = viz::CompositorRenderPass::Create();
 

cc/paint/paint_record.h

@@ -25,6 +25,8 @@ class CC_PAINT_EXPORT PaintRecord {
  public:
   PaintRecord();
   ~PaintRecord();
+  // After move, the source is invalid (with nullptr buffer_) and can't be
+  // used anymore.
   PaintRecord(PaintRecord&&);
   PaintRecord& operator=(PaintRecord&&);
   PaintRecord(const PaintRecord&);
@@ -34,7 +36,10 @@ class CC_PAINT_EXPORT PaintRecord {
     return buffer_->EqualsForTesting(*other.buffer_);
   }
 
-  const PaintOpBuffer& buffer() const { return *buffer_; }
+  const PaintOpBuffer& buffer() const {
+    CHECK(buffer_);
+    return *buffer_;
+  }
 
   size_t size() const { return buffer_->size(); }
   bool empty() const { return buffer_->empty(); }