Make length property return useful values for DOM bindings functions

LayoutTests/fast/js/constructor-length-expected.txt

Index: LayoutTests/fast/js/constructor-length-expected.txt
diff --git a/LayoutTests/fast/js/constructor-length-expected.txt b/LayoutTests/fast/js/constructor-length-expected.txt
index 6fc3b3361b2d7da976881020a9a3690aef9fb8c2..25cdd7a41d4d9eea65498ac1c7bed5c27dc1a236 100644
--- a/LayoutTests/fast/js/constructor-length-expected.txt
+++ b/LayoutTests/fast/js/constructor-length-expected.txt
@@ -3,54 +3,54 @@ This tests the length property of constructors.
 On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
 
 
-FAIL ArrayBuffer.length should be 1. Was 0.
+PASS ArrayBuffer.length is 1
 FAIL AudioContext.length should be 0. Threw exception ReferenceError: AudioContext is not defined
-FAIL AutocompleteErrorEvent.length should be 2. Was 0.
-FAIL BeforeLoadEvent.length should be 2. Was 0.
-FAIL Blob.length should be 2. Was 0.
-FAIL CloseEvent.length should be 2. Was 0.
-FAIL CustomEvent.length should be 2. Was 0.
+PASS AutocompleteErrorEvent.length is 1
+PASS BeforeLoadEvent.length is 1
+PASS Blob.length is 0
+PASS CloseEvent.length is 1
+PASS CustomEvent.length is 1
 FAIL DOMFormData.length should be 0. Threw exception ReferenceError: DOMFormData is not defined
 PASS DOMParser.length is 0
-FAIL DataView.length should be 3. Was 0.
-FAIL ErrorEvent.length should be 2. Was 0.
-FAIL Event.length should be 2. Was 0.
-FAIL EventSource.length should be 2. Was 0.
-FAIL Float32Array.length should be 1. Was 0.
-FAIL Float64Array.length should be 1. Was 0.
+PASS DataView.length is 1
+PASS ErrorEvent.length is 1
+PASS Event.length is 1
+PASS EventSource.length is 1
+PASS Float32Array.length is 1
+PASS Float64Array.length is 1
 PASS FileReader.length is 0
 FAIL FileReaderSync.length should be 0. Threw exception ReferenceError: FileReaderSync is not defined
-FAIL HashChangeEvent.length should be 2. Was 0.
-FAIL Int16Array.length should be 1. Was 0.
-FAIL Int32Array.length should be 1. Was 0.
-FAIL Int8Array.length should be 1. Was 0.
+PASS HashChangeEvent.length is 1
+PASS Int16Array.length is 1
+PASS Int32Array.length is 1
+PASS Int8Array.length is 1
 FAIL Intent.length should be 3. Threw exception ReferenceError: Intent is not defined
 PASS MediaController.length is 0
 FAIL MediaStream.length should be 0. Threw exception ReferenceError: MediaStream is not defined
 PASS MessageChannel.length is 0
-FAIL MessageEvent.length should be 2. Was 0.
-FAIL OverflowEvent.length should be 2. Was 0.
-FAIL PageTransitionEvent.length should be 2. Was 0.
+PASS MessageEvent.length is 1
+PASS OverflowEvent.length is 1
+PASS PageTransitionEvent.length is 1
 FAIL PeerConnection.length should be 2. Threw exception ReferenceError: PeerConnection is not defined
-FAIL PopStateEvent.length should be 2. Was 0.
-FAIL ProgressEvent.length should be 2. Was 0.
+PASS PopStateEvent.length is 1
+PASS ProgressEvent.length is 1
 FAIL ShadowRoot.length should be 1. Threw exception ReferenceError: ShadowRoot is not defined
 FAIL SharedWorker.length should be 2. Threw exception ReferenceError: SharedWorker is not defined
-FAIL StorageEvent.length should be 2. Was 0.
-FAIL TextTrackCue.length should be 3. Was 0.
-FAIL TrackEvent.length should be 2. Was 0.
-FAIL Uint16Array.length should be 1. Was 0.
-FAIL Uint32Array.length should be 1. Was 0.
-FAIL Uint8Array.length should be 1. Was 0.
-FAIL Uint8ClampedArray.length should be 1. Was 0.
-FAIL WebGLContextEvent.length should be 2. Was 0.
-FAIL WebKitAnimationEvent.length should be 2. Was 0.
-FAIL WebKitCSSMatrix.length should be 1. Was 0.
-FAIL WebKitMutationObserver.length should be 1. Was 0.
-FAIL WebKitPoint.length should be 2. Was 0.
-FAIL WebKitTransitionEvent.length should be 2. Was 0.
-FAIL WebSocket.length should be 1. Was 0.
-FAIL Worker.length should be 1. Was 0.
+PASS StorageEvent.length is 1
+PASS TextTrackCue.length is 3
+PASS TrackEvent.length is 1
+PASS Uint16Array.length is 1
+PASS Uint32Array.length is 1
+PASS Uint8Array.length is 1
+PASS Uint8ClampedArray.length is 1
+PASS WebGLContextEvent.length is 1
+PASS WebKitAnimationEvent.length is 1
+PASS WebKitCSSMatrix.length is 0
+PASS WebKitMutationObserver.length is 1
+PASS WebKitPoint.length is 0
+PASS WebKitTransitionEvent.length is 1
+PASS WebSocket.length is 1
+PASS Worker.length is 1
 PASS URL.length is 0
 PASS XMLHttpRequest.length is 0
 PASS XMLSerializer.length is 0