Release mouse pointer capture when it starts drag

third_party/WebKit/Source/core/input/EventHandler.cpp

Index: third_party/WebKit/Source/core/input/EventHandler.cpp
diff --git a/third_party/WebKit/Source/core/input/EventHandler.cpp b/third_party/WebKit/Source/core/input/EventHandler.cpp
index 89cbf41dababfdd287484efbe736920b2dd0150f..81b330ec472a9518a1da6f0a7aa12a351a3de323 100644
--- a/third_party/WebKit/Source/core/input/EventHandler.cpp
+++ b/third_party/WebKit/Source/core/input/EventHandler.cpp
@@ -564,6 +564,12 @@ OptionalCursor EventHandler::SelectAutoCursor(const HitTestResult& result,
   return PointerCursor();
 }
 
+WebInputEventResult EventHandler::HandlePointerEvent(
+    const WebPointerEvent& web_pointer_event,
+    Node* target) {
+  return pointer_event_manager_->HandlePointerEvent(web_pointer_event, target);
+}
+
 WebInputEventResult EventHandler::HandleMousePressEvent(
     const WebMouseEvent& mouse_event) {
   TRACE_EVENT0("blink", "EventHandler::handleMousePressEvent");