Reduce hit test on ShowPress by moving event targeting to WebViewImpl

public/web/WebInputEvent.h

Index: public/web/WebInputEvent.h
diff --git a/public/web/WebInputEvent.h b/public/web/WebInputEvent.h
index 58c4a0bb39e1d8230b7d4ec08ad94a54f7d0dde5..38b281837feef004c5bbb77e8c6ab092158b6cd8 100644
--- a/public/web/WebInputEvent.h
+++ b/public/web/WebInputEvent.h
@@ -477,6 +477,35 @@ public:
     {
         memset(&data, 0, sizeof(data));
     }
+
+    bool isScrollEvent() const
+    {
+        switch (type) {
+        case GestureScrollBegin:
+        case GestureScrollEnd:
+        case GestureScrollUpdate:
+        case GestureScrollUpdateWithoutPropagation:
+        case GestureFlingStart:
+        case GestureFlingCancel:
+        case GesturePinchBegin:
+        case GesturePinchEnd:
+        case GesturePinchUpdate:
+            return true;
+        case GestureShowPress:
+        case GestureTap:
+        case GestureTapUnconfirmed:
+        case GestureTapDown:
+        case GestureTapCancel:
+        case GestureDoubleTap:
+        case GestureTwoFingerTap:
+        case GestureLongPress:
+        case GestureLongTap:
+            return false;
+        default:
+            BLINK_ASSERT_NOT_REACHED();
+            return false;
+        }
+    }
 };
 
 // WebTouchEvent --------------------------------------------------------------