Fix WebSocket to set first party for cookies

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

Index: third_party/WebKit/Source/core/dom/Document.cpp
diff --git a/third_party/WebKit/Source/core/dom/Document.cpp b/third_party/WebKit/Source/core/dom/Document.cpp
index a49ef639f5d79ea62091a133211aff1bd8104ad3..b8fc83bbd3571c6af7b570e128d899f68e29eaa9 100644
--- a/third_party/WebKit/Source/core/dom/Document.cpp
+++ b/third_party/WebKit/Source/core/dom/Document.cpp
@@ -4170,10 +4170,15 @@ String Document::lastModified() const
 
 const KURL Document::firstPartyForCookies() const
 {
+    // TODO(mkwst): This doesn't properly handle HTML Import documents.
+
     // If this is an imported document, grab its master document's first-party:
     if (importsController() && importsController()->master() && importsController()->master() != this)
         return importsController()->master()->firstPartyForCookies();
 
+    if (!frame())
+        return SecurityOrigin::urlWithUniqueSecurityOrigin();
+
     // TODO(mkwst): This doesn't correctly handle sandboxed documents; we want to look at their URL,
     // but we can't because we don't know what it is.
     Frame* top = frame()->tree().top();