PreviewTab: Extend experiment flag/stats to M92

Extends the experiments to M92 so the flag options will be visible.

Also extended Search.ContextualSearch.SelectionExpanded while I'm at it.

Change-Id: If2466711bd67d1c692d0e1f3cec1fe2461f009e0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2472680Reviewed-by: Donn Denman <donnd@chromium.org>
Reviewed-by: Jesse Doherty <jwd@chromium.org>
Commit-Queue: Jinsuk Kim <jinsukkim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#817691}

chrome/browser/flag-metadata.json

@@ -1460,12 +1460,12 @@
   {
     "name": "enable-ephemeral-tab",
     "owners": [ "donnd", "jinsukkim" ],
-    "expiry_milestone": 90
+    "expiry_milestone": 92
   },
   {
     "name": "enable-ephemeral-tab-bottom-sheet",
     "owners": [ "donnd", "jinsukkim" ],
-    "expiry_milestone": 90
+    "expiry_milestone": 92
   },
   {
     "name": "enable-experimental-accessibility-chromevox-annotations",

tools/metrics/histograms/histograms_xml/others/histograms.xml

@@ -4462,7 +4462,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="EphemeralTab.BottomSheet.CloseReason"
-    enum="BottomSheet.StateChangeReason" expires_after="M88">
+    enum="BottomSheet.StateChangeReason" expires_after="M92">
   <owner>donnd@chromium.org</owner>
   <owner>jinsukkim@chromium.org</owner>
   <summary>
@@ -4472,7 +4472,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="EphemeralTab.CloseReason"
-    enum="OverlayPanel.StateChangeReason" expires_after="M88">
+    enum="OverlayPanel.StateChangeReason" expires_after="M92">
   <owner>donnd@chromium.org</owner>
   <owner>jinsukkim@chromium.org</owner>
   <summary>
@@ -4481,7 +4481,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
-<histogram name="EphemeralTab.Ctr" enum="BooleanOpened" expires_after="M88">
+<histogram name="EphemeralTab.Ctr" enum="BooleanOpened" expires_after="M92">
   <owner>donnd@chromium.org</owner>
   <owner>jinsukkim@chromium.org</owner>
   <summary>
@@ -4490,7 +4490,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
-<histogram name="EphemeralTab.CtrPeek" enum="BooleanOpened" expires_after="M88">
+<histogram name="EphemeralTab.CtrPeek" enum="BooleanOpened" expires_after="M92">
   <owner>donnd@chromium.org</owner>
   <owner>jinsukkim@chromium.org</owner>
   <summary>
@@ -4499,7 +4499,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
-<histogram name="EphemeralTab.DurationOpened" units="ms" expires_after="M88">
+<histogram name="EphemeralTab.DurationOpened" units="ms" expires_after="M92">
   <owner>donnd@chromium.org</owner>
   <owner>jinsukkim@chromium.org</owner>
   <summary>
@@ -4508,7 +4508,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
-<histogram name="EphemeralTab.DurationPeeked" units="ms" expires_after="M88">
+<histogram name="EphemeralTab.DurationPeeked" units="ms" expires_after="M92">
   <owner>donnd@chromium.org</owner>
   <owner>jinsukkim@chromium.org</owner>
   <summary>

tools/metrics/histograms/histograms_xml/search/histograms.xml

@@ -222,7 +222,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="Search.ContextualSearch.SelectionExpanded"
-    enum="ContextualSearchGestureIsTap" expires_after="M88">
+    enum="ContextualSearchGestureIsTap" expires_after="M92">
   <owner>donnd@chromium.org</owner>
   <owner>twellington@chromium.org</owner>
   <summary>