Revert of [Template Expressions] changing ${ leader to $i18n{

ui/base/template_expressions.h

Index: ui/base/template_expressions.h
diff --git a/ui/base/template_expressions.h b/ui/base/template_expressions.h
index a8ac908b18ffadf46e18077b42bd5d60b2694375..ff14ee1b719149e0286a24c728ec4b64a28a8d35 100644
--- a/ui/base/template_expressions.h
+++ b/ui/base/template_expressions.h
@@ -16,15 +16,12 @@
 
 namespace ui {
 
-// Map of strings for template replacement in |ReplaceTemplateExpressions|.
-typedef std::map<const std::string, std::string> TemplateReplacements;
-
 // Replace ${foo} in the format string with the value for the foo key in
 // |subst|.  If the key is not found in the |substitutions| that item will
 // be unaltered.
 UI_BASE_EXPORT std::string ReplaceTemplateExpressions(
     base::StringPiece format_string,
-    const TemplateReplacements& substitutions);
+    const std::map<base::StringPiece, std::string>& substitutions);
 
 }  // namespace ui