No pointer captured when the pointer lock is applied

third_party/WebKit/Source/core/dom/Element.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc.
  * All rights reserved.
  *           (C) 2007 Eric Seidel (eric@webkit.org)
  *
@@ skipping 3056 matching lines @@
       exception_state);
   if (!fragment)
     return;
   InsertAdjacent(where, fragment, exception_state);
 }
 
 void Element::setPointerCapture(int pointer_id,
                                 ExceptionState& exception_state) {
   if (GetDocument().GetFrame()) {
     if (!GetDocument().GetFrame()->GetEventHandler().IsPointerEventActive(
-            pointer_id))
+            pointer_id)) {
       exception_state.ThrowDOMException(kInvalidPointerId, "InvalidPointerId");
-    else if (!isConnected())
+    } else if (!isConnected()) {
       exception_state.ThrowDOMException(kInvalidStateError,
                                         "InvalidStateError");
-    else
+    } else if (GetDocument().GetPage() && GetDocument()

[mustaq, 2017/05/26 14:56:18]

Nit: Combine with the above |if| with an OR, since both throw the same
exception.

[lanwei, 2017/05/29 18:30:07]

Done.

+                                              .GetPage()
+                                              ->GetPointerLockController()
+                                              .GetElement()) {
+      exception_state.ThrowDOMException(kInvalidStateError,
+                                        "InvalidStateError");
+    } else {
       GetDocument().GetFrame()->GetEventHandler().SetPointerCapture(pointer_id,
                                                                     this);
+    }
   }
 }
 
 void Element::releasePointerCapture(int pointer_id,
                                     ExceptionState& exception_state) {
   if (GetDocument().GetFrame()) {
     if (!GetDocument().GetFrame()->GetEventHandler().IsPointerEventActive(
             pointer_id))
       exception_state.ThrowDOMException(kInvalidPointerId, "InvalidPointerId");
     else
@@ skipping 1253 matching lines @@
 }
 
 DEFINE_TRACE_WRAPPERS(Element) {
   if (HasRareData()) {
     visitor->TraceWrappers(GetElementRareData());
   }
   ContainerNode::TraceWrappers(visitor);
 }
 
 }  // namespace blink