Add new flag for experimental app banners.

tools/metrics/histograms/enums.xml

Index: tools/metrics/histograms/enums.xml
diff --git a/tools/metrics/histograms/enums.xml b/tools/metrics/histograms/enums.xml
index 9265cc9706ef270bac4782d534ada61e959e18d0..db94cfc1d791e0c8e33c5c88f443a34017222a13 100644
--- a/tools/metrics/histograms/enums.xml
+++ b/tools/metrics/histograms/enums.xml
@@ -22791,6 +22791,7 @@ from previous Chrome versions.
   <int value="477967119" label="enable-unified-media-pipeline"/>
   <int value="479906041" label="RunAllFlashInAllowMode:disabled"/>
   <int value="480544447" label="NonValidatingReloadOnRefreshContentV2:enabled"/>
+  <int value="492113129" label="ExperimentalAppBanners:enabled"/>
   <int value="493903641" label="disable-appcontainer"/>
   <int value="494733611" label="disable-drop-sync-credential"/>
   <int value="503245473" label="disable-translate-new-ux"/>
@@ -23119,6 +23120,7 @@ from previous Chrome versions.
   <int value="1612974229" label="allow-insecure-localhost"/>
   <int value="1617187093" label="enable-improved-a2hs"/>
   <int value="1622131033" label="ozone-test-single-overlay-support"/>
+  <int value="1626824478" label="ExperimentalAppBanners:disabled"/>
   <int value="1633456034" label="chrome-home-swipe-logic"/>
   <int value="1634897915" label="password-import-export:enabled"/>
   <int value="1636962093" label="disable-material-design-ntp"/>