Add a virtual test suite for exposed "stable" features

LayoutTests/virtual/webexposed/stable/global-constructors-listing-expected.txt

Index: LayoutTests/virtual/webexposed/stable/global-constructors-listing-expected.txt
diff --git a/LayoutTests/webexposed/global-constructors-listing-expected.txt b/LayoutTests/virtual/webexposed/stable/global-constructors-listing-expected.txt
similarity index 96%
copy from LayoutTests/webexposed/global-constructors-listing-expected.txt
copy to LayoutTests/virtual/webexposed/stable/global-constructors-listing-expected.txt
index 616445546203c551a77e8d66b277fb6994565476..b39dae068c8e2e0f9036fbfffe13d78587fb65b0 100644
--- a/LayoutTests/webexposed/global-constructors-listing-expected.txt
+++ b/LayoutTests/virtual/webexposed/stable/global-constructors-listing-expected.txt
@@ -65,7 +65,6 @@ DataTransferItemList
 DataView
 Date
 DelayNode
-DeviceMotionEvent
 DeviceOrientationEvent
 Document
 DocumentFragment
@@ -103,7 +102,6 @@ HTMLCollection
 HTMLContentElement
 HTMLDListElement
 HTMLDataListElement
-HTMLDialogElement
 HTMLDirectoryElement
 HTMLDivElement
 HTMLDocument
@@ -186,19 +184,12 @@ Int32Array
 Int8Array
 KeyboardEvent
 Location
-MIDIConnectionEvent
-MIDIMessageEvent
 MediaController
 MediaElementAudioSourceNode
 MediaError
 MediaKeyError
 MediaKeyEvent
-MediaKeyMessageEvent
-MediaKeyNeededEvent
-MediaKeySession
-MediaKeys
 MediaList
-MediaSource
 MediaStreamAudioDestinationNode
 MediaStreamAudioSourceNode
 MediaStreamEvent
@@ -227,7 +218,6 @@ Option
 OscillatorNode
 OverflowEvent
 PageTransitionEvent
-Path
 Performance
 PerformanceEntry
 PerformanceMark
@@ -241,8 +231,6 @@ PluginArray
 PopStateEvent
 ProcessingInstruction
 ProgressEvent
-Promise
-PromiseResolver
 RGBColor
 RTCIceCandidate
 RTCSessionDescription
@@ -396,23 +384,16 @@ SVGZoomEvent
 Screen
 ScriptProcessorNode
 SecurityPolicy
-SecurityPolicyViolationEvent
 Selection
-ShadowRoot
 SharedWorker
 SpeechInputEvent
-SpeechSynthesisEvent
-SpeechSynthesisUtterance
 Storage
 StorageEvent
-Stream
 String
 StyleSheet
 StyleSheetList
 SyntaxError
 Text
-TextDecoder
-TextEncoder
 TextEvent
 TextMetrics
 TextTrack
@@ -454,7 +435,6 @@ WebKitCSSKeyframeRule
 WebKitCSSKeyframesRule
 WebKitCSSMatrix
 WebKitCSSMixFunctionValue
-WebKitCSSRegionRule
 WebKitCSSTransformValue
 WebKitMediaSource
 WebKitMutationObserver