Introduce IncrementLoadEventDelayCount::clearAndCheckLoadEvent()

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

Index: third_party/WebKit/Source/core/dom/IncrementLoadEventDelayCount.cpp
diff --git a/third_party/WebKit/Source/core/dom/IncrementLoadEventDelayCount.cpp b/third_party/WebKit/Source/core/dom/IncrementLoadEventDelayCount.cpp
index 86b68d16f902219b921c60613365417f06873a91..fc85a1c9a8f6710c3a74ed38490df12fbbb8641a 100644
--- a/third_party/WebKit/Source/core/dom/IncrementLoadEventDelayCount.cpp
+++ b/third_party/WebKit/Source/core/dom/IncrementLoadEventDelayCount.cpp
@@ -21,12 +21,19 @@ IncrementLoadEventDelayCount::IncrementLoadEventDelayCount(Document& document)
 }
 
 IncrementLoadEventDelayCount::~IncrementLoadEventDelayCount() {
-  m_document->decrementLoadEventDelayCount();
+  if (m_document)
+    m_document->decrementLoadEventDelayCount();
+}
+
+void IncrementLoadEventDelayCount::clearAndCheckLoadEvent() {
+  m_document->decrementLoadEventDelayCountAndCheckLoadEvent();
+  m_document = nullptr;
 }
 
 void IncrementLoadEventDelayCount::documentChanged(Document& newDocument) {
   newDocument.incrementLoadEventDelayCount();
-  m_document->decrementLoadEventDelayCount();
+  if (m_document)
+    m_document->decrementLoadEventDelayCount();
   m_document = &newDocument;
 }
 }  // namespace blink