Revert "[ios] Remove Safety Check and Remote Tab resmption"

This reverts commit 75da352.

Reason for revert: Re-enabling both for Beta channels

Original change's description:
> [ios] Remove Safety Check and Remote Tab resmption
>
> Change-Id: I0314fb86b3bf65aa7048e37c8753e7ce68e6008d
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5069276
> Auto-Submit: Chris Lu <thegreenfrog@chromium.org>
> Commit-Queue: Ginny Huang <ginnyhuang@chromium.org>
> Reviewed-by: Ginny Huang <ginnyhuang@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1230678}

Change-Id: Ibd8e9699792aa48a9dda91fb874ac569ac8ff965
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5101164
Reviewed-by: Ginny Huang <ginnyhuang@chromium.org>
Commit-Queue: Chris Lu <thegreenfrog@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#1234724}

testing/variations/fieldtrial_testing_config.json

@@ -10293,11 +10293,12 @@
                         "ReducedNTPTopSpace": "20",
                         "SetUpListCompactedTimeThresholdDays": "0",
                         "enable_default_model": "true",
-                        "variant": "tab-resumption-recent-tab-only"
+                        "variant": "tab-resumption-all-tabs"
                     },
                     "enable_features": [
                         "IOSParcelTracking",
                         "MagicStack",
+                        "SafetyCheckMagicStack",
                         "SegmentationPlatformIosModuleRanker",
                         "SegmentationPlatformUserVisibleTaskRunner",
                         "TabResumption"