Add Streams API support to XMLHttpRequest

Source/core/fileapi/Stream.h

Index: Source/core/fileapi/Stream.h
diff --git a/Source/core/fileapi/Stream.h b/Source/core/fileapi/Stream.h
index 71d9d81d9340d4519c53bebdc975639093a2ef4e..d80cc2403cb4e5d2c237805bc1527568b5d30a42 100644
--- a/Source/core/fileapi/Stream.h
+++ b/Source/core/fileapi/Stream.h
@@ -58,6 +58,9 @@ public:
     // Mark this stream finalized so that a reader of this stream is notified
     // of EOF.
     void finalize();
+    // Mark this stream finalized due to an error so that a reader of this
+    // stream is notified of EOF due to the error.
+    void abort();
 
     // Allow an external reader class to mark this object neutered so that they
     // won't load the corresponding stream again. All stream objects are