Use downloadToFile option when XHR downloads a Blob

LayoutTests/http/tests/inspector/timeline-xhr-event-expected.txt

Index: LayoutTests/http/tests/inspector/timeline-xhr-event-expected.txt
diff --git a/LayoutTests/http/tests/inspector/timeline-xhr-event-expected.txt b/LayoutTests/http/tests/inspector/timeline-xhr-event-expected.txt
new file mode 100644
index 0000000000000000000000000000000000000000..03fe5fe98578145fb365d3a0419ac27120e6b5c0
--- /dev/null
+++ b/LayoutTests/http/tests/inspector/timeline-xhr-event-expected.txt
@@ -0,0 +1,58 @@
+Tests the Timeline events for XMLHttpReqeust
+
+XHRReadyStateChange Properties:
+{
+    children : <object>
+    counters : <object>
+    data : {
+        readyState : 2
+        url : .../inspector/network/resources/resource.php
+    }
+    endTime : <number>
+    frameId : <string>
+    startTime : <number>
+    type : "XHRReadyStateChange"
+    usedHeapSize : <number>
+}
+XHRReadyStateChange Properties:
+{
+    children : <object>
+    counters : <object>
+    data : {
+        readyState : 3
+        url : .../inspector/network/resources/resource.php
+    }
+    endTime : <number>
+    frameId : <string>
+    startTime : <number>
+    type : "XHRReadyStateChange"
+    usedHeapSize : <number>
+}
+XHRReadyStateChange Properties:
+{
+    children : <object>
+    counters : <object>
+    data : {
+        readyState : 4
+        url : .../inspector/network/resources/resource.php
+    }
+    endTime : <number>
+    frameId : <string>
+    startTime : <number>
+    type : "XHRReadyStateChange"
+    usedHeapSize : <number>
+}
+XHRLoad Properties:
+{
+    children : <object>
+    counters : <object>
+    data : {
+        url : .../inspector/network/resources/resource.php
+    }
+    endTime : <number>
+    frameId : <string>
+    startTime : <number>
+    type : "XHRLoad"
+    usedHeapSize : <number>
+}
+