[PDF Ink Signatures] Ignore inputs of a different type while stroking

Fix a crash where PdfInkModule::RecordStrokePosition() complains the
inputs are made with different tool types. Check the tool type and
ignore the event if the types are different.

Bug: 391387325
Change-Id: If5fec5a9ca5e4d2aa3a6d5c95f7194ba8a53e917
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6195922
Reviewed-by: Alan Screen <awscreen@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1415108}

pdf/pdf_ink_module.cc

@@ -516,6 +516,11 @@ bool PdfInkModule::ContinueStroke(const gfx::PointF& position,
     return true;
   }
 
+  if (state.input_last_event.value().tool_type != tool_type) {
+    // Ignore if the user is simultaneously using a different input type.
+    return true;
+  }
+
   const int page_index = client_->VisiblePageIndexFromPoint(position);
   const int last_page_index = client_->VisiblePageIndexFromPoint(last_position);
   if (page_index != state.page_index && last_page_index != state.page_index) {

pdf/pdf_ink_module_unittest.cc

@@ -1262,6 +1262,33 @@ TEST_F(PdfInkModuleStrokeTest, AnnotationWithMouseInterruptedByPenEvents) {
                    /*page_index=*/0, ink::StrokeInput::ToolType::kStylus));
 }
 
+TEST_F(PdfInkModuleStrokeTest, AnnotationWithPenIgnoresMouseEvents) {
+  EnableAnnotationMode();
+  InitializeSimpleSinglePageBasicLayout();
+
+  blink::WebTouchEvent pen_start_event =
+      CreatePenEvent(blink::WebInputEvent::Type::kTouchStart,
+                     base::span_from_ref(kMouseDownPoint));
+  EXPECT_TRUE(ink_module().HandleInputEvent(pen_start_event));
+
+  blink::WebMouseEvent mouse_move_event =
+      CreateMouseMoveWithLeftButtonEventAtPoint(kMouseMovePoint);
+  EXPECT_TRUE(ink_module().HandleInputEvent(mouse_move_event));
+
+  blink::WebTouchEvent pen_end_event =
+      CreatePenEvent(blink::WebInputEvent::Type::kTouchEnd,
+                     base::span_from_ref(kMouseUpPoint));
+  EXPECT_TRUE(ink_module().HandleInputEvent(pen_end_event));
+
+  EXPECT_EQ(1, client().stroke_finished_count());
+  EXPECT_EQ(0, ink_module().GetInputOfTypeCountForPageForTesting(
+                   /*page_index=*/0, ink::StrokeInput::ToolType::kMouse));
+  EXPECT_EQ(0, ink_module().GetInputOfTypeCountForPageForTesting(
+                   /*page_index=*/0, ink::StrokeInput::ToolType::kTouch));
+  EXPECT_EQ(2, ink_module().GetInputOfTypeCountForPageForTesting(
+                   /*page_index=*/0, ink::StrokeInput::ToolType::kStylus));
+}
+
 TEST_F(PdfInkModuleStrokeTest, CanonicalAnnotationPoints) {
   // Setup to support examining the page stroke points for a layout that is
   // more complicated than what is provide by