Directly inline shared WebUI CSS declarations into the security and supervised user interstitials.

ui/base/webui/web_ui_util.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_BASE_WEBUI_WEB_UI_UTIL_H_
 #define UI_BASE_WEBUI_WEB_UI_UTIL_H_
 
 #include <string>
 
 #include "base/strings/string_piece.h"
@@ skipping 27 matching lines @@
 // Pares a formatted scale factor string into float and sets to |scale_factor|.
 UI_BASE_EXPORT bool ParseScaleFactor(const base::StringPiece& identifier,
                                      float* scale_factor);
 
 // Parses a URL containing some path @{scale}x. If it does not contain a scale
 // factor then the default scale factor is returned.
 UI_BASE_EXPORT void ParsePathAndScale(const GURL& url,
                                       std::string* path,
                                       float* scale_factor);
 
-// Helper function to set the font family, size, and text direction into the
-// given dictionary.
-UI_BASE_EXPORT void SetFontAndTextDirection(
-    base::DictionaryValue* localized_strings);
+// Helper function to set the text direction on the given dictionary.
+// Note that while this method will also set attributes for default font size
+// and family, using those in JS templates is deprecated, because it might lead
+// to flicker. Instead, use AppendWebUICSSTextDefaults() below.
+// TODO(bauerb): Remove uses of font-family and font-size in JS templates.
+UI_BASE_EXPORT void SetTextDirection(base::DictionaryValue* localized_strings);
+
+// Get a CSS declaration for common text styles for all of Web UI.
+UI_BASE_EXPORT std::string GetWebUICSSTextDefaults();
+
+// Appends the CSS declaration returned by GetWebUICSSTextDefaults() as an
+// inline stylesheet.
+UI_BASE_EXPORT void AppendWebUICSSTextDefaults(std::string* html);
 
 // Get some common font styles for all of WebUI.
 UI_BASE_EXPORT std::string GetFontFamily();
 UI_BASE_EXPORT std::string GetFontSize();
 UI_BASE_EXPORT std::string GetTextDirection();
 
 }  // namespace webui
 
 #endif  // UI_BASE_WEBUI_WEB_UI_UTIL_H_