Add UMA for the new uninstall dialog.

BUG=1009248

Change-Id: I9253de4ba310849dc52d0615c211ca11bb9dc548
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1859418Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Bret Sepulveda <bsep@chromium.org>
Commit-Queue: Nancy Wang <nancylingwang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#707757}

chrome/browser/ui/browser_dialogs.h

@@ -252,6 +252,7 @@ enum class DialogIdentifier {
   PHONE_CHOOSER = 98,
   QR_CODE_GENERATOR = 99,
   CROSTINI_FORCE_CLOSE = 100,
+  APP_UNINSTALL = 101,
   // Add values above this line with a corresponding label in
   // tools/metrics/histograms/enums.xml
   MAX_VALUE

chrome/browser/ui/views/apps/app_uninstall_dialog_view.cc

@@ -7,6 +7,7 @@
 #include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/ui/browser_dialogs.h"
 #include "chrome/browser/ui/views/chrome_layout_provider.h"
 #include "chrome/browser/ui/views/chrome_typography.h"
 #include "chrome/common/extensions/manifest_handlers/app_launch_info.h"
@@ -53,6 +54,8 @@ AppUninstallDialogView::AppUninstallDialogView(
       app_name_(app_name) {
   InitializeView(profile, app_id);
   constrained_window::CreateBrowserModalDialogViews(this, nullptr)->Show();
+
+  chrome::RecordDialogCreation(chrome::DialogIdentifier::APP_UNINSTALL);
 }
 
 bool AppUninstallDialogView::Cancel() {

tools/metrics/histograms/enums.xml

@@ -13974,6 +13974,7 @@ Called by update_net_error_codes.py.-->
   <int value="98" label="Phone Chooser"/>
   <int value="99" label="QR Code Generator"/>
   <int value="100" label="Crostini Force Close"/>
+  <int value="101" label="App Uninstall"/>
 </enum>
 
 <enum name="DialogOriginRelationship">