[CORS-RFC1918] Add WebFeatures to UKM allowlist.

These will be used to determine the path forward to an eventual removal
of the feature in the NonSecure case, and a rollout of CORS-RFC1918 in
the Secure case.

These features are not yet recorded, but we know that the event rate
will not exceed 1% of page loads. Indeed these features are
finer-grained replacements for the now-obsolete
LoopbackEmbeddedIn{Non,}SecureContext feature, which average less than
0.003% combined on Windows Stable.

Bug: chromium:1124358
Change-Id: Ie53327654907d4b3ee8d88b91cceb957a8640602
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2436823Reviewed-by: John Delaney <johnidel@chromium.org>
Reviewed-by: Jesse Doherty <jwd@chromium.org>
Reviewed-by: Mike West <mkwst@chromium.org>
Commit-Queue: Jesse Doherty <jwd@chromium.org>
Auto-Submit: Titouan Rigoudy <titouan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812357}

chrome/browser/page_load_metrics/page_load_metrics_browsertest.cc

@@ -1642,7 +1642,7 @@ IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest,
 
   const auto& entries = test_ukm_recorder_->GetEntriesByName(
       ukm::builders::Blink_UseCounter::kEntryName);
-  EXPECT_EQ(4u, entries.size());
+  EXPECT_EQ(5u, entries.size());
   std::vector<int64_t> ukm_features;
   for (const auto* entry : entries) {
     test_ukm_recorder_->ExpectEntrySourceHasUrl(entry, url);
@@ -1660,7 +1660,10 @@ IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest,
           static_cast<int64_t>(WebFeature::kFullscreenSecureOrigin),
           static_cast<int64_t>(WebFeature::kNavigatorVibrate),
           static_cast<int64_t>(
-              WebFeature::kApplicationCacheManifestSelectSecureOrigin)));
+              WebFeature::kApplicationCacheManifestSelectSecureOrigin),
+          static_cast<int64_t>(
+              WebFeature::
+                  kAddressSpaceLocalEmbeddedInUnknownNonSecureContext)));
 }
 
 // Test UseCounter UKM mixed content features observed.
@@ -1683,7 +1686,7 @@ IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTestWithAutoupgradesDisabled,
 
   const auto& entries = test_ukm_recorder_->GetEntriesByName(
       ukm::builders::Blink_UseCounter::kEntryName);
-  EXPECT_EQ(7u, entries.size());
+  EXPECT_EQ(8u, entries.size());
   std::vector<int64_t> ukm_features;
   for (const auto* entry : entries) {
     test_ukm_recorder_->ExpectEntrySourceHasUrl(entry, url);
@@ -1694,16 +1697,20 @@ IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTestWithAutoupgradesDisabled,
     DCHECK(metric);
     ukm_features.push_back(*metric);
   }
-  EXPECT_THAT(ukm_features,
-              UnorderedElementsAre(
-                  static_cast<int64_t>(WebFeature::kPageVisits),
-                  static_cast<int64_t>(WebFeature::kFullscreenSecureOrigin),
-                  static_cast<int64_t>(WebFeature::kNavigatorVibrate),
-                  static_cast<int64_t>(
-                      WebFeature::kApplicationCacheManifestSelectSecureOrigin),
-                  static_cast<int64_t>(WebFeature::kMixedContentImage),
-                  static_cast<int64_t>(WebFeature::kMixedContentAudio),
-                  static_cast<int64_t>(WebFeature::kMixedContentVideo)));
+  EXPECT_THAT(
+      ukm_features,
+      UnorderedElementsAre(
+          static_cast<int64_t>(WebFeature::kPageVisits),
+          static_cast<int64_t>(WebFeature::kFullscreenSecureOrigin),
+          static_cast<int64_t>(WebFeature::kNavigatorVibrate),
+          static_cast<int64_t>(
+              WebFeature::kApplicationCacheManifestSelectSecureOrigin),
+          static_cast<int64_t>(WebFeature::kMixedContentImage),
+          static_cast<int64_t>(WebFeature::kMixedContentAudio),
+          static_cast<int64_t>(WebFeature::kMixedContentVideo),
+          static_cast<int64_t>(
+              WebFeature::
+                  kAddressSpaceLocalEmbeddedInUnknownNonSecureContext)));
 }
 
 // Test UseCounter Features observed in a child frame are recorded, exactly

components/page_load_metrics/browser/observers/use_counter/ukm_features.cc

@@ -169,6 +169,16 @@ UseCounterPageLoadMetricsObserver::GetAllowedUkmFeatures() {
           WebFeature::kSchemelesslySameSitePostMessageSecureToInsecure,
           WebFeature::kSchemelesslySameSitePostMessageInsecureToSecure,
           WebFeature::kElementAttachInternalsBeforeConstructor,
+          WebFeature::kAddressSpaceLocalEmbeddedInPrivateSecureContext,
+          WebFeature::kAddressSpaceLocalEmbeddedInPrivateNonSecureContext,
+          WebFeature::kAddressSpaceLocalEmbeddedInPublicSecureContext,
+          WebFeature::kAddressSpaceLocalEmbeddedInPublicNonSecureContext,
+          WebFeature::kAddressSpaceLocalEmbeddedInUnknownSecureContext,
+          WebFeature::kAddressSpaceLocalEmbeddedInUnknownNonSecureContext,
+          WebFeature::kAddressSpacePrivateEmbeddedInPublicSecureContext,
+          WebFeature::kAddressSpacePrivateEmbeddedInPublicNonSecureContext,
+          WebFeature::kAddressSpacePrivateEmbeddedInUnknownSecureContext,
+          WebFeature::kAddressSpacePrivateEmbeddedInUnknownNonSecureContext,
       }));
   return *opt_in_features;
-}
\ No newline at end of file
+}