doc.write intervention warning message changed to replace cross-origin with cross site (etdl+1)

chrome/browser/page_load_metrics/observers/document_write_page_load_metrics_observer.cc

Index: chrome/browser/page_load_metrics/observers/document_write_page_load_metrics_observer.cc
diff --git a/chrome/browser/page_load_metrics/observers/document_write_page_load_metrics_observer.cc b/chrome/browser/page_load_metrics/observers/document_write_page_load_metrics_observer.cc
index dbb8ac05af090d9e729de2e8a1d8634c5095f1d3..e0a510fd153787cc2df35123dbf87c70d7cd59bd 100644
--- a/chrome/browser/page_load_metrics/observers/document_write_page_load_metrics_observer.cc
+++ b/chrome/browser/page_load_metrics/observers/document_write_page_load_metrics_observer.cc
@@ -70,10 +70,14 @@ const char kBackgroundHistogramDocWriteBlockParseDuration[] =
 const char kHistogramDocWriteBlockReloadCount[] =
     "PageLoad.Clients.DocWrite.Block.ReloadCount";
 
+const char kHistogramDocWriteBlockSameSiteDiffSchemeCount[] =
+    "PageLoad.Clients.DocWrite.Block.SameSiteDiffSchemeCount";
+
 }  // namespace internal
 
 DocumentWritePageLoadMetricsObserver::DocumentWritePageLoadMetricsObserver()
-    : doc_write_block_reload_observed_(false) {}
+    : doc_write_block_reload_observed_(false),
+      doc_write_block_same_site_diff_scheme_(false) {}
 
 void DocumentWritePageLoadMetricsObserver::OnFirstContentfulPaint(
     const page_load_metrics::PageLoadTiming& timing,
@@ -126,6 +130,17 @@ void DocumentWritePageLoadMetricsObserver::OnLoadingBehaviorObserved(
     UMA_HISTOGRAM_COUNTS(internal::kHistogramDocWriteBlockReloadCount, 1);
     doc_write_block_reload_observed_ = true;
   }
+  if ((info.metadata.behavior_flags &
+       blink::WebLoadingBehaviorFlag::
+           WebLoadingBehaviorDocumentWriteBlockDifferentScheme) &&
+      !doc_write_block_same_site_diff_scheme_) {
+    DCHECK(
+        !(info.metadata.behavior_flags &
+          blink::WebLoadingBehaviorFlag::WebLoadingBehaviorDocumentWriteBlock));
+    UMA_HISTOGRAM_COUNTS(
+        internal::kHistogramDocWriteBlockSameSiteDiffSchemeCount, 1);
+    doc_write_block_same_site_diff_scheme_ = true;
+  }
 }
 
 void DocumentWritePageLoadMetricsObserver::