Cleanly detach XHR and other pending loader clients from Inspector.

third_party/WebKit/Source/core/xmlhttprequest/XMLHttpRequest.cpp

Index: third_party/WebKit/Source/core/xmlhttprequest/XMLHttpRequest.cpp
diff --git a/third_party/WebKit/Source/core/xmlhttprequest/XMLHttpRequest.cpp b/third_party/WebKit/Source/core/xmlhttprequest/XMLHttpRequest.cpp
index 5e72a29c9afc3c8ba06b9c108e09435ff03696a5..b55fd3f6a8cea1eb785193392a3b829aa9ece13a 100644
--- a/third_party/WebKit/Source/core/xmlhttprequest/XMLHttpRequest.cpp
+++ b/third_party/WebKit/Source/core/xmlhttprequest/XMLHttpRequest.cpp
@@ -1094,10 +1094,7 @@ void XMLHttpRequest::abort() {
 }
 
 void XMLHttpRequest::dispose() {
-  if (m_loader) {
-    m_error = true;
-    m_loader->cancel();
-  }
+  contextDestroyed(getExecutionContext());

[haraken, 2017/01/27 09:47:57]

I'd prefer not manually calling contextDestroyed (it should be called only by
LifecycleNotifer). Can we instead make contextDestroyed() call dispose()?

[sof, 2017/01/27 10:19:59]

ok, adjusted.

 }
 
 void XMLHttpRequest::clearVariablesForLoading() {
@@ -1118,6 +1115,12 @@ void XMLHttpRequest::clearVariablesForLoading() {
 }
 
 bool XMLHttpRequest::internalAbort() {
+  // Fast path for repeated internalAbort()s; this
+  // will happen if an XHR object is notified of context
+  // destruction followed by finalization.
+  if (m_error && !m_loader)
+    return true;
+
   m_error = true;
 
   if (m_responseDocumentParser && !m_responseDocumentParser->isStopped())
@@ -1807,9 +1810,8 @@ void XMLHttpRequest::resume() {
   m_progressEventThrottle->resume();
 }
 
-void XMLHttpRequest::contextDestroyed(ExecutionContext*) {
-  InspectorInstrumentation::didFailXHRLoading(getExecutionContext(), this, this,
-                                              m_method, m_url);
+void XMLHttpRequest::contextDestroyed(ExecutionContext* context) {
+  InspectorInstrumentation::detachClientRequest(context, this);
   m_progressEventThrottle->stop();
   internalAbort();