[Extensions Metrics] Refresh expiration on toolbar actions metrics

Update toolbar actions metrics:
- Remove Toolbar.ActionsModel.ToolbarActionsVisible. It's redundant with
  ExtensionToolbarModel.BrowserActionsVisible.
- Push back expiration on Toolbar.ActionsModel.ToolbarActionsVisible,
  and ExtensionToolbarModel.BrowserActionsCount to December 2019.

Bug: 975789
Change-Id: Iea2e548f90fa3f8a16dd25b8cff9c25dbb270997
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1683362Reviewed-by: Ilya Sherman <isherman@chromium.org>
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#675842}

chrome/browser/ui/toolbar/toolbar_actions_model.cc

@@ -551,11 +551,6 @@ void ToolbarActionsModel::Populate() {
                              visible_icon_count_ == -1
                                  ? base::HistogramBase::kSampleType_MAX
                                  : visible_icon_count_);
-
-    UMA_HISTOGRAM_COUNTS_100("Toolbar.ActionsModel.ToolbarActionsVisible",
-                             visible_icon_count_ == -1
-                                 ? base::HistogramBase::kSampleType_MAX
-                                 : visible_icon_count_);
   }
 }
 

tools/metrics/histograms/histograms.xml

@@ -42626,8 +42626,10 @@ uploading your change for review.
   </summary>
 </histogram>
 
-<histogram name="ExtensionToolbarModel.BrowserActionsCount" expires_after="M77">
-  <owner>finnur@chromium.org</owner>
+<histogram name="ExtensionToolbarModel.BrowserActionsCount"
+    expires_after="2019-12-01">
+  <owner>rdevlin.cronin@chromium.org</owner>
+  <owner>extensions-core@chromium.org</owner>
   <summary>
     The number of icons the Browser Actions Container knows about (visible or in
     the overflow bucket). Does not count icons that have been permanently hidden
@@ -42646,8 +42648,9 @@ uploading your change for review.
 </histogram>
 
 <histogram name="ExtensionToolbarModel.BrowserActionsVisible"
-    expires_after="M77">
-  <owner>finnur@chromium.org</owner>
+    expires_after="2019-12-01">
+  <owner>rdevlin.cronin@chromium.org</owner>
+  <owner>extensions-core@chromium.org</owner>
   <summary>
     The number of visible icons in the Browser Actions Container (visible as in
     number of icons not in the overflow bucket). 0 means all icons are in the
@@ -136958,8 +136961,11 @@ should be kept until we use this API.  -->
   </summary>
 </histogram>
 
-<histogram name="Toolbar.ActionsModel.ToolbarActionsVisible"
-    expires_after="2020-12-01">
+<histogram name="Toolbar.ActionsModel.ToolbarActionsVisible">
+  <obsolete>
+    Obsolete. See ExtensionToolbarModel.BrowserActionsVisible instead. Stopped
+    recording 2019-07.
+  </obsolete>
   <owner>rdevlin.cronin@chromium.org</owner>
   <owner>extensions-core@chromium.org</owner>
   <summary>