[Cleanup] Move all browsertests to use ScopedFeatureList to modify features

chrome/browser/page_load_metrics/observers/ads_page_load_metrics_observer.h

Index: chrome/browser/page_load_metrics/observers/ads_page_load_metrics_observer.h
diff --git a/chrome/browser/page_load_metrics/observers/ads_page_load_metrics_observer.h b/chrome/browser/page_load_metrics/observers/ads_page_load_metrics_observer.h
index 3e42a42ef9dbcaddc7f9826b0d1223913729dff2..92d7fa01bf64579508685f8ea5cd3510952957a9 100644
--- a/chrome/browser/page_load_metrics/observers/ads_page_load_metrics_observer.h
+++ b/chrome/browser/page_load_metrics/observers/ads_page_load_metrics_observer.h
@@ -9,11 +9,18 @@
 #include <map>
 #include <memory>
 
+#include "base/feature_list.h"
 #include "base/macros.h"
 #include "chrome/browser/page_load_metrics/page_load_metrics_observer.h"
 #include "components/ukm/ukm_source.h"
 #include "net/http/http_response_info.h"
 
+namespace features {
+
+extern const base::Feature kAdsFeature;
+
+}  // namespace features

[Ilya Sherman, 2017/06/12 21:50:29]

Same, for this and other features that you'd like to have public visibility
within //chrome.

[chaopeng, 2017/06/28 19:21:24]

Done.

+
 // This observer labels each sub-frame as an ad or not, and keeps track of
 // relevant per-frame and whole-page byte statistics.
 class AdsPageLoadMetricsObserver