Revert "macOS V2 GPU Sandbox: Diagnose mach service hang."

This reverts commit a521561e.

Reason for revert: very likely cause for https://crbug.com/960763

Original change's description:
> macOS V2 GPU Sandbox: Diagnose mach service hang.
> 
> This is a temporary CL to locate and diagnose a mach service acccess
> that is hanging.
> 
> Bug: 871280
> Change-Id: I8ef068baa2f6f4b6eb3dd7a15671dffc399db2dc
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1599251
> Commit-Queue: Greg Kerr <kerrnel@chromium.org>
> Commit-Queue: Robert Sesek <rsesek@chromium.org>
> Auto-Submit: Greg Kerr <kerrnel@chromium.org>
> Reviewed-by: Robert Sesek <rsesek@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#657377}

TBR=kerrnel@chromium.org,rsesek@chromium.org

Change-Id: Ie2351b19805c898a2809aad094bc8345f17abc0b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 871280
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1600835Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#657672}

services/service_manager/sandbox/mac/gpu_v2.sb

@@ -86,16 +86,6 @@
   (subpath "/System/Library/Video/Plug-Ins")
 )
 
-; A temporary test to diagnose a hang - crbug.com/871280
+; A temporary test to diagnose a hang.
 (if (string=? (param bundle-id) "com.google.Chrome.canary")
-  (begin
-    (deny (with no-log) mach-lookup
-      (global-name "com.apple.cfprefsd.daemon")
-      (global-name "com.apple.GameController.gamecontrollerd")
-      (global-name "com.apple.bsd.dirhelper")
-      (global-name "com.apple.system.opendirectoryd.membership")
-      (global-name "com.apple.powerlog.plxpclogger.xpc")
-      (global-name "com.apple.PowerManagement.control")
-    )
-    (deny mach-lookup (with send-signal SIGFPE)))
-)
+  (allow mach-lookup))