Drop -webkit-user-select in favor of user-select

Bug: chromium:1031475
Change-Id: Ibbf222135c97e79ae3be816216fec9675d643952
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/1953613
Commit-Queue: Mathias Bynens <[email protected]>
Commit-Queue: Changhao Han <[email protected]>
Auto-Submit: Mathias Bynens <[email protected]>
Reviewed-by: Changhao Han <[email protected]>
diff --git a/front_end/network/webSocketFrameView.css b/front_end/network/webSocketFrameView.css
index 257a625..2f7e145 100644
--- a/front_end/network/webSocketFrameView.css
+++ b/front_end/network/webSocketFrameView.css
@@ -5,7 +5,7 @@
  */
 
 .websocket-frame-view {
-    -webkit-user-select: text;
+    user-select: text;
 }
 
 .websocket-frame-view .data-grid {