Remove unused "Web" interfaces

sky/engine/public/BUILD.gn

Index: sky/engine/public/BUILD.gn
diff --git a/sky/engine/public/BUILD.gn b/sky/engine/public/BUILD.gn
index 9c2aadaded3208d131f7b7ce08e433c02e70153a..0000b3d50fb2960be51693afb03c9f503acc6238 100644
--- a/sky/engine/public/BUILD.gn
+++ b/sky/engine/public/BUILD.gn
@@ -99,15 +99,11 @@ source_set("platform_headers") {
 source_set("web_headers") {
   public = [
     "web/Sky.h",
-    "web/WebActiveWheelFlingParameters.h",
-    "web/WebArrayBufferConverter.h",
-    "web/WebArrayBufferView.h",
     "web/WebBeginFrameArgs.h",
     "web/WebCache.h",
     "web/WebCachedURLRequest.h",
     "web/WebCompositionUnderline.h",
     "web/WebConsoleMessage.h",
-    "web/WebContentDetectionResult.h",
     "web/WebDocument.h",
     "web/WebElement.h",
     "web/WebExceptionCode.h",
@@ -115,13 +111,9 @@ source_set("web_headers") {
     "web/WebFontDescription.h",
     "web/WebFrame.h",
     "web/WebFrameClient.h",
-    "web/WebGlyphCache.h",
     "web/WebHitTestResult.h",
-    "web/WebImageCache.h",
-    "web/WebImageDecoder.h",
     "web/WebLeakDetector.h",
     "web/WebLocalFrame.h",
-    "web/WebMemoryUsageInfo.h",
     "web/WebNavigationPolicy.h",
     "web/WebNavigationType.h",
     "web/WebNavigatorContentUtilsClient.h",
@@ -129,12 +121,9 @@ source_set("web_headers") {
     "web/WebPageVisibilityState.h",
     "web/WebRange.h",
     "web/WebRuntimeFeatures.h",
-    "web/WebScriptBindings.h",
-    "web/WebScriptController.h",
     "web/WebScriptSource.h",
     "web/WebSettings.h",
     "web/WebSpellCheckClient.h",
-    "web/WebTestingSupport.h",
     "web/WebTextAffinity.h",
     "web/WebTextCheckingCompletion.h",
     "web/WebTextCheckingResult.h",