Add the webview zygote socket to the zygote whitelist.

Allow the webview zygote socket to be open at time of fork, so that
webview renderers can be forked successfully.

(cherry picked from commit a7fcb2bc2a)

Test: WebView functions correctly with multiprocess dev setting enabled
Bug: 21643067
Change-Id: I312846433a43a8e4548cb2f98b96b56acf9f5333

core/jni/fd_utils-inl.h

@@ -51,6 +51,7 @@ static const char* kPathWhitelist[] = {
   "/dev/null",
   "/dev/socket/zygote",
   "/dev/socket/zygote_secondary",
+  "/dev/socket/webview_zygote",
   "/sys/kernel/debug/tracing/trace_marker",
   "/system/framework/framework-res.apk",
   "/dev/urandom",