Fix FLEDGE for chrome://flags/#privacy-sandbox-ads-apis.

Tested against the repro in crbug.com/1311254.

(cherry picked from commit 1f7e921)

Bug: 1311254
Change-Id: Ic77e559cd92552a95b6538eb05e9b48ab1dd52c2
Fixed: 1311254
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3558276
Reviewed-by: John Delaney <johnidel@chromium.org>
Commit-Queue: Caleb Raitto <caraitto@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#987139}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3560540
Reviewed-by: Krishna Govind <govind@chromium.org>
Commit-Queue: Krishna Govind <govind@chromium.org>
Owners-Override: Krishna Govind <govind@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/branch-heads/4974@{#8}
Cr-Branched-From: 89f4767-refs/heads/main@{#986924}

chrome/browser/about_flags.cc

@@ -7128,7 +7128,9 @@ const FeatureEntry kFeatureEntries[] = {
      // multiple related features when they are available.
      SINGLE_VALUE_TYPE_AND_VALUE(switches::kEnableFeatures,
                                  "PrivacySandboxAdsAPIsOverride,"
-                                 "Fledge,BrowsingTopics,ConversionMeasurement,"
+                                 "InterestGroupStorage,Fledge,"
+                                 "AllowURNsInIframes,BrowsingTopics,"
+                                 "ConversionMeasurement,"
                                  "OverridePrivacySandboxSettingsLocalTesting")},
 
     {"animated-image-resume", flag_descriptions::kAnimatedImageResumeName,