Move WebInputEvent from public/web to public/platform

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 ec5f6e3658c68d4f31c1073b07ed62c32d7d7ebf..bc93e8bd1c3146f37487f9da2e66969681a3722e 100644
--- a/sky/engine/public/BUILD.gn
+++ b/sky/engine/public/BUILD.gn
@@ -59,6 +59,7 @@ source_set("platform_headers") {
     "platform/WebHTTPLoadInfo.h",
     "platform/WebImage.h",
     "platform/WebImageLayer.h",
+    "platform/WebInputEvent.h",
     "platform/WebLayer.h",
     "platform/WebLayerScrollClient.h",
     "platform/WebLayerTreeView.h",
@@ -76,6 +77,7 @@ source_set("platform_headers") {
     "platform/WebSize.h",
     "platform/WebString.h",
     "platform/WebThread.h",
+    "platform/WebTouchPoint.h",
     "platform/WebTransformAnimationCurve.h",
     "platform/WebTransformKeyframe.h",
     "platform/WebTransformOperations.h",
@@ -119,7 +121,6 @@ source_set("web_headers") {
     "web/WebHitTestResult.h",
     "web/WebImageCache.h",
     "web/WebImageDecoder.h",
-    "web/WebInputEvent.h",
     "web/WebLeakDetector.h",
     "web/WebLocalFrame.h",
     "web/WebMemoryUsageInfo.h",
@@ -147,7 +148,6 @@ source_set("web_headers") {
     "web/WebTextInputType.h",
     "web/WebTextRun.h",
     "web/WebTouchAction.h",
-    "web/WebTouchPoint.h",
     "web/WebURLLoaderOptions.h",
     "web/WebUserGestureIndicator.h",
     "web/WebUserGestureToken.h",