new method GetExtantDocument. bug 36016 r=hyatt,pinkerton

dom/public/base/nsPIDOMWindow.h

@@ -44,7 +44,6 @@
 #include "nsString.h"
 #include "nsIScriptContext.h"
 #include "nsIDOMLocation.h"
-#include "nsPIDOMWindow.h"
 #include "nsIDOMXULCommandDispatcher.h"
 #include "nsIDocument.h"
 
@@ -81,6 +80,9 @@ public:
 
   NS_IMETHOD GetRootFocusController(nsIFocusController** aResult) = 0;
 
+  // GetExtantDocument provides a backdoor to the DOM GetDocument accessor
+  NS_IMETHOD GetExtantDocument(nsIDOMDocument** aDocument) = 0;
+
   NS_IMETHOD ReallyCloseWindow() = 0;
 };
 

dom/src/base/nsGlobalWindow.cpp

@@ -776,6 +776,15 @@ NS_IMETHODIMP GlobalWindowImpl::GetDocument(nsIDOMDocument** aDocument)
   return NS_OK;
 }
 
+// like GetDocument, but merely fetches the document if it already exists
+NS_IMETHODIMP GlobalWindowImpl::GetExtantDocument(nsIDOMDocument** aDocument)
+{
+  NS_ENSURE_ARG_POINTER(aDocument);
+  *aDocument = mDocument;
+  NS_IF_ADDREF(*aDocument);
+  return NS_OK;
+}
+
 //*****************************************************************************
 // GlobalWindowImpl::nsIDOMWindowInternal
 //*****************************************************************************

dom/src/base/nsGlobalWindow.h

@@ -181,6 +181,8 @@ public:
                                   PRBool* aResult);
   NS_IMETHOD SetMutationListeners(PRUint32 aEventType);
   NS_IMETHOD GetRootFocusController(nsIFocusController** aResult);
+  NS_IMETHOD GetExtantDocument(nsIDOMDocument** aDocument);
+
   NS_IMETHOD ReallyCloseWindow();
 
   // nsIDOMViewCSS