Disable handle zapping

Bug=chromium:318206
TBR=machenbach@chromium.org
NOTRY=true
NOPRESUBMIT=true

Change-Id: Ib28c17e0d08985813b0ba8136fb747714e80a599
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1571611
Reviewed-by: Michael Hablich <hablich@chromium.org>
Commit-Queue: Michael Hablich <hablich@chromium.org>
Cr-Commit-Position: refs/branch-heads/7.5@{#2}
Cr-Branched-From: 35b9bf5-refs/heads/7.5.288@{#1}
Cr-Branched-From: 912b391-refs/heads/master@{#60911}

BUILD.gn

@@ -77,7 +77,7 @@ declare_args() {
   v8_enable_vtunejit = false
 
   # Sets -dENABLE_HANDLE_ZAPPING.
-  v8_enable_handle_zapping = true
+  v8_enable_handle_zapping = is_debug
 
   # Enable slow dchecks.
   v8_enable_slow_dchecks = false