Form validation: Validation bubble should be closed on document unload process.

third_party/WebKit/Source/web/ValidationMessageClientImpl.cpp

Index: third_party/WebKit/Source/web/ValidationMessageClientImpl.cpp
diff --git a/third_party/WebKit/Source/web/ValidationMessageClientImpl.cpp b/third_party/WebKit/Source/web/ValidationMessageClientImpl.cpp
index 294af072b5f51f7b529614fbedc162655bf87a40..c740f75145ad894c1fb50a5118102daf7c623ebc 100644
--- a/third_party/WebKit/Source/web/ValidationMessageClientImpl.cpp
+++ b/third_party/WebKit/Source/web/ValidationMessageClientImpl.cpp
@@ -111,11 +111,16 @@ bool ValidationMessageClientImpl::isValidationMessageVisible(
   return m_currentAnchor == &anchor;
 }
 
-void ValidationMessageClientImpl::documentDetached(const Document& document) {
+void ValidationMessageClientImpl::willUnloadDocument(const Document& document) {
   if (m_currentAnchor && m_currentAnchor->document() == document)
     hideValidationMessage(*m_currentAnchor);
 }
 
+void ValidationMessageClientImpl::documentDetached(const Document& document) {
+  DCHECK(!m_currentAnchor || m_currentAnchor->document() != document)
+      << "willUnloadDocument() should be called beforehand.";
+}
+
 void ValidationMessageClientImpl::checkAnchorStatus(TimerBase*) {
   DCHECK(m_currentAnchor);
   if (monotonicallyIncreasingTime() >= m_finishTime || !currentView()) {