Removes flag --enable-new-md-input-view and add a opposite flag: --disable-new-md-input-view.

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 7668dd6d6a28fdbef77acf4e9ab8b5da61c39e9b..35721f01471f283b795ff324e23f1e2c81697d18 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -52984,6 +52984,7 @@ To add a new entry, add it with any value and run test to compute valid value.
   <int value="-1285021473" label="save-page-as-mhtml"/>
   <int value="-1268836676" label="disable-out-of-process-pdf"/>
   <int value="-1267958145" label="disable-pdf-material-ui"/>
+  <int value="-1251411236" label="disable-new-md-input-view"/>
   <int value="-1241747717" label="enable-android-password-link"/>
   <int value="-1218608640" label="disable-offline-load-stale-cache"/>
   <int value="-1216837777" label="clear-data-reduction-proxy-data-savings"/>
@@ -53123,7 +53124,6 @@ To add a new entry, add it with any value and run test to compute valid value.
   <int value="401983950" label="enable-spdy4"/>
   <int value="402143634" label="enable-search-button-in-omnibox-always"/>
   <int value="412957264" label="tab-close-buttons-hidden-with-touch"/>
-  <int value="413081240" label="enable-new-md-input-view"/>
   <int value="415154056" label="enable-physical-keyboard-autocorrect"/>
   <int value="423615350" label="enable-tab-audio-muting"/>
   <int value="446316019" label="enable-threaded-compositing"/>