Revert "[iOS] Fix incorrect flag name for OmniboxOnFocusSuggestions"

This reverts commit 723e06ee.

Reason for revert: There was a name mismatch, but it wasn't here. It was on the Finch config end.

Original change's description:
> [iOS] Fix incorrect flag name for OmniboxOnFocusSuggestions
> 
> Because the name was incorrect here, when Finch sends a config for this
> Feature, both the gws_id from Finch and the gws_id defined in
> about_flags were sent back to gws. If an enabled and a disabled ID are
> sent to gws, the disabled id is the one that takes affect, so the
> feature ends up disabled.
> 
> Bug: 1071078
> Change-Id: Ic67f1d5415ac5895a84ee41adc8b2c98d1c38456
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2153106
> Reviewed-by: Rohit Rao <rohitrao@chromium.org>
> Commit-Queue: Robbie Gibson <rkgibson@google.com>
> Cr-Commit-Position: refs/heads/master@{#759983}

TBR=rohitrao@chromium.org,rkgibson@google.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 1071078
Change-Id: I9ac014ef320a1c7ae19634d37aca03f66bf570a9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2156547Reviewed-by: Robbie Gibson <rkgibson@google.com>
Commit-Queue: Robbie Gibson <rkgibson@google.com>
Cr-Commit-Position: refs/heads/master@{#760928}

ios/chrome/browser/flags/about_flags.mm

@@ -382,7 +382,7 @@ const flags_ui::FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kOmniboxOnFocusSuggestionsDescription, flags_ui::kOsIos,
      FEATURE_WITH_PARAMS_VALUE_TYPE(omnibox::kOnFocusSuggestions,
                                     kOmniboxOnFocusSuggestionsVariations,
-                                    "OmniboxOnFocusSuggestions")},
+                                    "OmniboxBundledExperimentV1")},
     {"omnibox-ui-max-autocomplete-matches",
      flag_descriptions::kOmniboxUIMaxAutocompleteMatchesName,
      flag_descriptions::kOmniboxUIMaxAutocompleteMatchesDescription,