chrome/blink: Add functionality for in-product help for media elements.

components/feature_engagement_tracker/public/feature_list.h

Index: components/feature_engagement_tracker/public/feature_list.h
diff --git a/components/feature_engagement_tracker/public/feature_list.h b/components/feature_engagement_tracker/public/feature_list.h
index a815e40e484313681c137852b4513dc1cf7d544a..f8fa96ea966d387e0b7bf75963fda546b33bc4cd 100644
--- a/components/feature_engagement_tracker/public/feature_list.h
+++ b/components/feature_engagement_tracker/public/feature_list.h
@@ -51,6 +51,7 @@ DEFINE_VARIATION_PARAM(kIPHDownloadHomeFeature, "IPH_DownloadHome");
 DEFINE_VARIATION_PARAM(kIPHDownloadPageFeature, "IPH_DownloadPage");
 DEFINE_VARIATION_PARAM(kIPHDownloadPageScreenshotFeature,
                        "IPH_DownloadPageScreenshot");
+DEFINE_VARIATION_PARAM(kIPHMediaDownloadFeature, "IPH_MediaDownload");
 #endif  // defined(OS_ANDROID)
 #if defined(OS_WIN) || defined(OS_LINUX)
 DEFINE_VARIATION_PARAM(kIPHIncognitoWindowFeature, "IPH_IncognitoWindow");
@@ -75,6 +76,7 @@ constexpr flags_ui::FeatureEntry::FeatureVariation
         VARIATION_ENTRY(kIPHDownloadHomeFeature),
         VARIATION_ENTRY(kIPHDownloadPageFeature),
         VARIATION_ENTRY(kIPHDownloadPageScreenshotFeature),
+        VARIATION_ENTRY(kIPHMediaDownloadFeature),
 #elif defined(OS_WIN) || defined(OS_LINUX)
         VARIATION_ENTRY(kIPHIncognitoWindowFeature),
         VARIATION_ENTRY(kIPHNewTabFeature),