[Extensions UI] Update button in settings overridden prompts

Instead of "Ignore", use "Keep it".

Bug: 1079364
Tbr: treib@chromium.org (per offline discussion)
Change-Id: I8905d3576b129a064d124007fa1ed9317c280ed8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2253367Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Reviewed-by: Marc Treib <treib@chromium.org>
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#780192}

chrome/app/generated_resources.grd

@@ -4646,8 +4646,8 @@ Keep your key file in a safe place. You will need it to create new versions of y
       <message name="IDS_EXTENSION_SETTINGS_OVERRIDDEN_DIALOG_CHANGE_IT_BACK" desc="The text of the button to revert to old settings; displayed in the dialog describing settings overridden by an extension.">
         Change it back
       </message>
-      <message name="IDS_EXTENSION_SETTINGS_OVERRIDDEN_DIALOG_IGNORE" desc="The text of the button to ignore the settings changes, allowing the extension changes to remain in effect. Displayed in the dialog describing settings overridden by an extension.">
-        Ignore
+      <message name="IDS_EXTENSION_SETTINGS_OVERRIDDEN_DIALOG_KEEP_IT" desc="The text of the button to ignore the settings changes, allowing the extension changes to remain in effect. Displayed in the dialog describing settings overridden by an extension.">
+        Keep it
       </message>
       <message name="IDS_EXTENSION_NTP_OVERRIDDEN_DIALOG_TITLE_GENERIC" desc="The title of the dialog informing the user that the new tab page has been overridden by an extension.">
         Did you mean to change this page?

chrome/app/generated_resources_grd/IDS_EXTENSION_SETTINGS_OVERRIDDEN_DIALOG_IGNORE.png.sha1

-21758524a99a3da77a4246d1c676a3cae62813fb
\ No newline at end of file

chrome/app/generated_resources_grd/IDS_EXTENSION_SETTINGS_OVERRIDDEN_DIALOG_KEEP_IT.png.sha1

+817d67dce56468511fada902c156d0d20f466cbd
\ No newline at end of file

chrome/browser/ui/views/extensions/settings_overridden_dialog_view.cc

@@ -25,7 +25,7 @@ SettingsOverriddenDialogView::SettingsOverriddenDialogView(
                      IDS_EXTENSION_SETTINGS_OVERRIDDEN_DIALOG_CHANGE_IT_BACK));
   SetButtonLabel(ui::DIALOG_BUTTON_CANCEL,
                  l10n_util::GetStringUTF16(
-                     IDS_EXTENSION_SETTINGS_OVERRIDDEN_DIALOG_IGNORE));
+                     IDS_EXTENSION_SETTINGS_OVERRIDDEN_DIALOG_KEEP_IT));
   SetLayoutManager(std::make_unique<views::FillLayout>());
   ChromeLayoutProvider* const layout_provider = ChromeLayoutProvider::Get();
   set_margins(