Allow zygote to setpgid on webview_zygote.

Bug: 73720684
Bug: 73720684
Test: m
Test: BootTest on taimen
Change-Id: I5a58fd1cce568cc50ba791f445f5c148eb87b474

private/zygote.te

@@ -25,6 +25,7 @@ allow zygote appdomain:file { r_file_perms };
 # Move children into the peer process group.
 allow zygote system_server:process { getpgid setpgid };
 allow zygote appdomain:process { getpgid setpgid };
+allow zygote webview_zygote:process { getpgid setpgid };
 
 # Read system data.
 allow zygote system_data_file:dir r_dir_perms;