Migrate the one-time notice into the MD settings CBD dialog

chrome/browser/ui/webui/settings/settings_clear_browsing_data_handler.cc

Index: chrome/browser/ui/webui/settings/settings_clear_browsing_data_handler.cc
diff --git a/chrome/browser/ui/webui/settings/settings_clear_browsing_data_handler.cc b/chrome/browser/ui/webui/settings/settings_clear_browsing_data_handler.cc
index b3da547c0127cbce1c742528a22b03c8b3d96a01..b0431637b9685c9830576a1bdfd5893af144e33e 100644
--- a/chrome/browser/ui/webui/settings/settings_clear_browsing_data_handler.cc
+++ b/chrome/browser/ui/webui/settings/settings_clear_browsing_data_handler.cc
@@ -21,11 +21,18 @@
 #include "chrome/browser/browsing_data/passwords_counter.h"
 #include "chrome/browser/history/web_history_service_factory.h"
 #include "chrome/browser/sync/profile_sync_service_factory.h"
+#include "chrome/common/channel_info.h"
 #include "chrome/common/pref_names.h"
 #include "components/browsing_data_ui/history_notice_utils.h"
 #include "components/prefs/pref_service.h"
 #include "content/public/browser/web_ui.h"
 
+namespace {
+
+const int kMaxTimesHistoryNoticeShown = 1;
+
+}
+
 namespace settings {
 
 ClearBrowsingDataHandler::ClearBrowsingDataHandler(content::WebUI* webui)
@@ -166,9 +173,33 @@ void ClearBrowsingDataHandler::HandleClearBrowsingData(
 void ClearBrowsingDataHandler::OnBrowsingDataRemoverDone() {
   remover_->RemoveObserver(this);
   remover_ = nullptr;
+
+  PrefService* prefs = profile_->GetPrefs();
+  int notice_shown_times =
+      prefs->GetInteger(prefs::kClearBrowsingDataHistoryNoticeShownTimes);
+
+  // When the deletion is complete, we might show an additional dialog with
+  // a notice about other forms of browsing history. This is the case if
+  const bool show_notice =
+      // 1. The dialog is relevant for the user.
+      should_show_history_deletion_dialog_ &&
+      // 2. The selected data types contained browsing history.
+      prefs->GetBoolean(prefs::kDeleteBrowsingHistory) &&
+      // 3. The notice has been shown less than |kMaxTimesHistoryNoticeShown|.
+      notice_shown_times < kMaxTimesHistoryNoticeShown;

[dschuyler, 2016/06/25 01:34:54]

nit: not a big deal, but if #2 and #3 were swapped,
we may avoid calling prefs-GetBoolean when
notice_shown_times < kMaxTimesHistoryNoticeShown
is false.

[msramek, 2016/06/27 15:24:59]

Done.

+
+  if (show_notice) {
+    // Increment the preference.
+    prefs->SetInteger(prefs::kClearBrowsingDataHistoryNoticeShownTimes,
+                      notice_shown_times + 1);

[dschuyler, 2016/06/25 01:34:54]

trivia: it looks like there is a potential race
condition here. It also looks like the effect of
that race are harmless. This note is just to ask
that it be given consideration (whether the race
is an issue). If (as I expect) it's harmless, then
an 'ack' on this note is plenty.

[msramek, 2016/06/27 15:24:59]

Acknowledged. Thanks for pointing it out.

+  }
+
+  UMA_HISTOGRAM_BOOLEAN(
+      "History.ClearBrowsingData.ShownHistoryNoticeAfterClearing", show_notice);
+
   ResolveJavascriptCallback(
       base::StringValue(webui_callback_id_),
-      *base::Value::CreateNullValue());
+      base::FundamentalValue(show_notice));
   webui_callback_id_.clear();
 }
 
@@ -210,6 +241,21 @@ void ClearBrowsingDataHandler::RefreshHistoryNotice() {
       WebHistoryServiceFactory::GetForProfile(profile_),
       base::Bind(&ClearBrowsingDataHandler::UpdateHistoryNotice,
                  weak_ptr_factory_.GetWeakPtr()));
+
+  // If the dialog with history notice has been shown less than
+  // |kMaxTimesHistoryNoticeShown| times, we might have to show it when the
+  // user deletes history. Find out if the conditions are met.
+  int notice_shown_times = profile_->GetPrefs()->
+      GetInteger(prefs::kClearBrowsingDataHistoryNoticeShownTimes);
+
+  if (notice_shown_times < kMaxTimesHistoryNoticeShown) {
+    browsing_data_ui::ShouldPopupDialogAboutOtherFormsOfBrowsingHistory(
+        sync_service_,
+        WebHistoryServiceFactory::GetForProfile(profile_),
+        chrome::GetChannel(),
+        base::Bind(&ClearBrowsingDataHandler::UpdateHistoryDeletionDialog,
+                   weak_ptr_factory_.GetWeakPtr()));
+  }
 }
 
 void ClearBrowsingDataHandler::UpdateHistoryNotice(bool show) {
@@ -221,6 +267,11 @@ void ClearBrowsingDataHandler::UpdateHistoryNotice(bool show) {
       should_show_history_footer_);
 }
 
+void ClearBrowsingDataHandler::UpdateHistoryDeletionDialog(bool show) {
+  // This is used by OnBrowsingDataRemoverDone (when the deletion finishes).
+  should_show_history_deletion_dialog_ = show;
+}
+
 void ClearBrowsingDataHandler::AddCounter(
     std::unique_ptr<BrowsingDataCounter> counter) {
   counter->Init(