Add a virtual test suite for exposed "stable" features

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

Index: LayoutTests/virtual/stable/webexposed/global-constructors-listing-expected.txt
diff --git a/LayoutTests/webexposed/global-constructors-listing-expected.txt b/LayoutTests/virtual/stable/webexposed/global-constructors-listing-expected.txt
similarity index 96%
copy from LayoutTests/webexposed/global-constructors-listing-expected.txt
copy to LayoutTests/virtual/stable/webexposed/global-constructors-listing-expected.txt
index 0f44a0cea1fade555ef6575139411dc6dfd6e0c1..941d68d711070167bad796cf9304941f03f6262e 100644
--- a/LayoutTests/webexposed/global-constructors-listing-expected.txt
+++ b/LayoutTests/virtual/stable/webexposed/global-constructors-listing-expected.txt
@@ -66,7 +66,6 @@ DataTransferItemList
 DataView
 Date
 DelayNode
-DeviceMotionEvent
 DeviceOrientationEvent
 Document
 DocumentFragment
@@ -104,7 +103,6 @@ HTMLCollection
 HTMLContentElement
 HTMLDListElement
 HTMLDataListElement
-HTMLDialogElement
 HTMLDirectoryElement
 HTMLDivElement
 HTMLDocument
@@ -187,19 +185,12 @@ Int32Array
 Int8Array
 KeyboardEvent
 Location
-MIDIConnectionEvent
-MIDIMessageEvent
 MediaController
 MediaElementAudioSourceNode
 MediaError
 MediaKeyError
 MediaKeyEvent
-MediaKeyMessageEvent
-MediaKeyNeededEvent
-MediaKeySession
-MediaKeys
 MediaList
-MediaSource
 MediaStreamAudioDestinationNode
 MediaStreamAudioSourceNode
 MediaStreamEvent
@@ -228,7 +219,6 @@ Option
 OscillatorNode
 OverflowEvent
 PageTransitionEvent
-Path
 Performance
 PerformanceEntry
 PerformanceMark
@@ -242,8 +232,6 @@ PluginArray
 PopStateEvent
 ProcessingInstruction
 ProgressEvent
-Promise
-PromiseResolver
 RGBColor
 RTCIceCandidate
 RTCSessionDescription
@@ -397,23 +385,16 @@ SVGZoomEvent
 Screen
 ScriptProcessorNode
 SecurityPolicy
-SecurityPolicyViolationEvent
 Selection
-ShadowRoot
 SharedWorker
 SpeechInputEvent
-SpeechSynthesisEvent
-SpeechSynthesisUtterance
 Storage
 StorageEvent
-Stream
 String
 StyleSheet
 StyleSheetList
 SyntaxError
 Text
-TextDecoder
-TextEncoder
 TextEvent
 TextMetrics
 TextTrack
@@ -455,7 +436,6 @@ WebKitCSSKeyframeRule
 WebKitCSSKeyframesRule
 WebKitCSSMatrix
 WebKitCSSMixFunctionValue
-WebKitCSSRegionRule
 WebKitCSSTransformValue
 WebKitMediaSource
 WebKitMutationObserver