MD History: UI polish pass

* Remove 'Psst' notice from delete confirmation dialog
* Increase line-height of 'other forms of history' notice to 20px

BUG=425625
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2195263002
Cr-Commit-Position: refs/heads/master@{#408911}

chrome/browser/resources/md_history/side_bar.html

@@ -88,6 +88,7 @@
       #footer-text {
         -webkit-padding-end: 16px;
         -webkit-padding-start: 24px;
+        line-height: 20px;
         margin: 24px 0;
       }
 

chrome/browser/ui/webui/history_ui.cc

@@ -101,8 +101,14 @@ content::WebUIDataSource* CreateHistoryUIHTMLSource(Profile* profile) {
   source->AddLocalizedString("clearAllHistory",
                              IDS_HISTORY_OPEN_CLEAR_BROWSING_DATA_DIALOG);
 
-  source->AddString("deleteWarning",
-                    HistoryUI::GetDeleteWarningString(profile));
+  auto availability = IncognitoModePrefs::GetAvailability(profile->GetPrefs());
+  base::string16 delete_string = availability == IncognitoModePrefs::ENABLED
+             ? l10n_util::GetStringFUTF16(
+                   IDS_HISTORY_DELETE_PRIOR_VISITS_WARNING,
+                   base::UTF8ToUTF16(kIncognitoModeShortcut))
+             : l10n_util::GetStringUTF16(
+                   IDS_HISTORY_DELETE_PRIOR_VISITS_WARNING_NO_INCOGNITO);
+  source->AddString("deleteWarning", delete_string);
 
   source->AddLocalizedString("removeBookmark", IDS_HISTORY_REMOVE_BOOKMARK);
   source->AddLocalizedString("actionMenuDescription",
@@ -199,14 +205,3 @@ base::RefCountedMemory* HistoryUI::GetFaviconResourceBytes(
   return ResourceBundle::GetSharedInstance().
       LoadDataResourceBytesForScale(IDR_HISTORY_FAVICON, scale_factor);
 }
-
-// static
-base::string16 HistoryUI::GetDeleteWarningString(Profile* profile) {
-  auto availability = IncognitoModePrefs::GetAvailability(profile->GetPrefs());
-  return availability == IncognitoModePrefs::ENABLED
-             ? l10n_util::GetStringFUTF16(
-                   IDS_HISTORY_DELETE_PRIOR_VISITS_WARNING,
-                   base::UTF8ToUTF16(kIncognitoModeShortcut))
-             : l10n_util::GetStringUTF16(
-                   IDS_HISTORY_DELETE_PRIOR_VISITS_WARNING_NO_INCOGNITO);
-}

chrome/browser/ui/webui/history_ui.h

@@ -23,10 +23,6 @@ class HistoryUI : public content::WebUIController {
   static base::RefCountedMemory* GetFaviconResourceBytes(
       ui::ScaleFactor scale_factor);
 
-  // Returns a localized string warning about deleting history. Takes into
-  // account whether or not incognito mode is available.
-  static base::string16 GetDeleteWarningString(Profile* profile);
-
  private:
   DISALLOW_COPY_AND_ASSIGN(HistoryUI);
 };

chrome/browser/ui/webui/md_history_ui.cc

@@ -11,7 +11,6 @@
 #include "chrome/browser/ui/webui/browsing_history_handler.h"
 #include "chrome/browser/ui/webui/foreign_session_handler.h"
 #include "chrome/browser/ui/webui/history_login_handler.h"
-#include "chrome/browser/ui/webui/history_ui.h"
 #include "chrome/browser/ui/webui/metrics_handler.h"
 #include "chrome/browser/ui/webui/settings/people_handler.h"
 #include "chrome/common/chrome_features.h"
@@ -48,6 +47,8 @@ content::WebUIDataSource* CreateMdHistoryUIHTMLSource(Profile* profile) {
   source->AddLocalizedString("delete", IDS_MD_HISTORY_DELETE);
   source->AddLocalizedString("deleteConfirm",
                              IDS_HISTORY_DELETE_PRIOR_VISITS_CONFIRM_BUTTON);
+  source->AddLocalizedString(
+      "deleteWarning", IDS_HISTORY_DELETE_PRIOR_VISITS_WARNING_NO_INCOGNITO);
   source->AddLocalizedString("foundSearchResults",
                              IDS_HISTORY_FOUND_SEARCH_RESULTS);
   source->AddLocalizedString("historyInterval", IDS_HISTORY_INTERVAL);
@@ -84,8 +85,6 @@ content::WebUIDataSource* CreateMdHistoryUIHTMLSource(Profile* profile) {
                              IDS_MD_HISTORY_SIGN_IN_PROMO_DESC);
   source->AddLocalizedString("title", IDS_HISTORY_TITLE);
 
-  source->AddString("deleteWarning",
-                    HistoryUI::GetDeleteWarningString(profile));
   source->AddString(
       "sidebarFooter",
       l10n_util::GetStringFUTF16(