PM: Enable service worker relationships for Albatross build.

This will get us DCHECK and CHECK failures from the field, and if needed
we can add additional instrumentation to figure out what's going on.

Bug: 1143281
Change-Id: I83c8c4470a71d195970673a3cc8c1ff1efd264e8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2611524Reviewed-by: Patrick Monette <pmonette@chromium.org>
Commit-Queue: Sigurður Ásgeirsson <siggi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#840264}

components/performance_manager/features.cc

@@ -7,6 +7,7 @@
 
 #include "components/performance_manager/public/features.h"
 
+#include "base/dcheck_is_on.h"
 #include "base/metrics/field_trial_params.h"
 
 namespace performance_manager {
@@ -47,7 +48,16 @@ TabLoadingFrameNavigationThrottlesParams::GetParams() {
 }
 
 const base::Feature kServiceWorkerRelationshipsInGraph{
-    "ServiceWorkerRelationshipsInGraph", base::FEATURE_DISABLED_BY_DEFAULT};
+  "ServiceWorkerRelationshipsInGraph",
+#if DCHECK_IS_ON()
+      // Enable service worker relationships by default under debug builds in
+      // order to get DCHECK failures from Alabatross.
+      // TODO(https://crbug.com/1143281): Revert once there's sufficient data.
+      base::FEATURE_ENABLED_BY_DEFAULT
+#else
+      base::FEATURE_DISABLED_BY_DEFAULT
+#endif
+};
 
 }  // namespace features
 }  // namespace performance_manager