Uses and returns the fractional width in text eliding

ui/gfx/font_list.cc

Index: ui/gfx/font_list.cc
diff --git a/ui/gfx/font_list.cc b/ui/gfx/font_list.cc
index 72c877754e59bfeeba9bf63af3ad8f652385d7af..cd8abc173af2cc2478f9019e16eecdd3f0932725 100644
--- a/ui/gfx/font_list.cc
+++ b/ui/gfx/font_list.cc
@@ -195,6 +195,13 @@ int FontList::GetStringWidth(const base::string16& text) const {
   return GetPrimaryFont().GetStringWidth(text);
 }
 
+float FontList::GetStringWidthF(const base::string16& text) const {

[Alexei Svitkine (slow), 2013/10/07 21:43:39]

Do we need this? Or can everything that needs it use gfx::GetStringWidthF() and
avoid introducing this API?

[jianli, 2013/10/07 23:18:45]

Done.

+  // Rely on the primary font metrics for the time being.
+  // TODO(yukishiino): Not only the first font, all the fonts in the list should
+  // be taken into account to compute the pixels needed to display |text|.
+  return GetPrimaryFont().GetStringWidthF(text);
+}
+
 int FontList::GetExpectedTextWidth(int length) const {
   // Rely on the primary font metrics for the time being.
   return GetPrimaryFont().GetExpectedTextWidth(length);