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

ui/base/webui/web_ui_util.h

Index: ui/base/webui/web_ui_util.h
diff --git a/ui/base/webui/web_ui_util.h b/ui/base/webui/web_ui_util.h
index 84e06f3170be5d3e336a932458efc5d5447f4f25..955ede0d198ca20bd7249111b407f92b475b28de 100644
--- a/ui/base/webui/web_ui_util.h
+++ b/ui/base/webui/web_ui_util.h
@@ -47,9 +47,18 @@ UI_BASE_EXPORT void ParsePathAndScale(const GURL& url,
 
 // Helper function to set the font family, size, and text direction into the
 // given dictionary.
+// Note that using JS templates to set these attributes might lead to flicker.
+// An alternative is to use AppendWebUICSSTextDefaults() below.

[felt, 2015/01/10 01:00:41]

nit: If this is being deprecated, should it say so here (for ex "Deprecated in
favor of AppendWebUICSSTextDefaults")?

[Bernhard Bauer, 2015/01/12 15:47:17]

Per Jungshik's comment in supervised_user_block_interstitial.html, we can't
completely deprecate this method. I've renamed it to SetTextDirection() and
mentioned the fact that other usage is deprecated.

 UI_BASE_EXPORT void SetFontAndTextDirection(
     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();