[ash-md] Erases the pre-MD code path for Overview Mode

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 6b38741b1c42684cbc4efe6a3a8ca52982f8d5a9..3edb78d6e633cc3d44b3d63923daf9a1606c8393 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -88036,7 +88036,6 @@ value.
   <int value="-213518852" label="protect-sync-credential:enabled"/>
   <int value="-206393363" label="enable-scroll-prediction"/>
   <int value="-204355195" label="secondary-ui-md"/>
-  <int value="-201208150" label="ash-max-previews-to-use-mask"/>
   <int value="-192919826" label="ViewsSimplifiedFullscreenUI:enabled"/>
   <int value="-183246373" label="enable-multilingual-spellchecker"/>
   <int value="-181093956" label="ScrollAnchoring:enabled"/>
@@ -88064,7 +88063,6 @@ value.
   <int value="-52241456" label="enable-single-click-autofill"/>
   <int value="-48920737" label="enable-smooth-scrolling"/>
   <int value="-45074716" label="SystemDownloadManager:disabled"/>
-  <int value="-45063580" label="ash-max-previews-to-use-shape"/>
   <int value="-23090520" label="disable-search-button-in-omnibox"/>
   <int value="-22544408" label="enable-video-player-chromecast-support"/>
   <int value="-13918890" label="disable-download-notification"/>