Do not increase the pointer id when type is eraser

third_party/WebKit/Source/core/events/PointerEventFactory.cpp

Index: third_party/WebKit/Source/core/events/PointerEventFactory.cpp
diff --git a/third_party/WebKit/Source/core/events/PointerEventFactory.cpp b/third_party/WebKit/Source/core/events/PointerEventFactory.cpp
index 2bbb8654d16dd90a4ce7f35ef1766e82490ffa2c..0d8e5df7ae9ec5f728d0ff244a0430af71f3f458 100644
--- a/third_party/WebKit/Source/core/events/PointerEventFactory.cpp
+++ b/third_party/WebKit/Source/core/events/PointerEventFactory.cpp
@@ -483,20 +483,29 @@ int PointerEventFactory::AddIdAndActiveButtons(const IncomingId p,
     return kMouseId;
   }
 
-  if (pointer_incoming_id_mapping_.Contains(p)) {
-    int mapped_id = pointer_incoming_id_mapping_.at(p);
-    pointer_id_mapping_.Set(mapped_id, PointerAttributes(p, is_active_buttons));
+  IncomingId incoming_id = p;
+  if (p.GetPointerType() == WebPointerProperties::PointerType::kEraser) {

[dtapuska, 2017/05/09 13:24:45]

Sorry this seems wrong to me. In that if we get an kEraser pointer type first
and then release it then you will end up incrementing the pointer ID. In that
the eraser pointer id != pen pointer id.

Can we just treat the creation of IncomingId if the type is kEraser as kPen?

+    const IncomingId pen_id =
+        IncomingId(WebPointerProperties::PointerType::kPen, p.RawId());
+    if (pointer_incoming_id_mapping_.Contains(pen_id))
+      incoming_id = pen_id;
+  }
+
+  if (pointer_incoming_id_mapping_.Contains(incoming_id)) {
+    int mapped_id = pointer_incoming_id_mapping_.at(incoming_id);
+    pointer_id_mapping_.Set(mapped_id,
+                            PointerAttributes(incoming_id, is_active_buttons));
     return mapped_id;
   }
-  int type_int = p.PointerTypeInt();
+  int type_int = incoming_id.PointerTypeInt();
   // We do not handle the overflow of m_currentId as it should be very rare
   int mapped_id = current_id_++;
   if (!id_count_[type_int])
     primary_id_[type_int] = mapped_id;
   id_count_[type_int]++;
-  pointer_incoming_id_mapping_.insert(p, mapped_id);
+  pointer_incoming_id_mapping_.insert(incoming_id, mapped_id);
   pointer_id_mapping_.insert(mapped_id,
-                             PointerAttributes(p, is_active_buttons));
+                             PointerAttributes(incoming_id, is_active_buttons));
   return mapped_id;
 }