Uses and returns the fractional width in text eliding

ui/gfx/canvas.h

Index: ui/gfx/canvas.h
diff --git a/ui/gfx/canvas.h b/ui/gfx/canvas.h
index 9aa7a0a4e4d6cc126b000520ea9bbca9afcd91f3..4646841e21e54f67215f1abc6491ef53d438afa9 100644
--- a/ui/gfx/canvas.h
+++ b/ui/gfx/canvas.h
@@ -139,6 +139,14 @@ class GFX_EXPORT Canvas {
                             int line_height,
                             int flags);
 
+  // This is same as SizeStringInt except that fractional size is returned.

[sky, 2013/10/08 02:12:56]

Please add a comment here and any public API you're adding about when and why
someone would want the float methods. Feel free to document this once (maybe
Font is the right place) and see look at XXX for when you would use this.

[jianli, 2013/10/08 18:29:48]

Added comment in Canvas::GetStringWidthF. We do not make any new addition to
Font class any more.

+  static void SizeStringFloat(const base::string16& text,
+                              const FontList& font_list,
+                              float* width,
+                              float* height,
+                              int line_height,
+                              int flags);
+
   // Returns the number of horizontal pixels needed to display the specified
   // |text| with |font_list|.
   static int GetStringWidth(const base::string16& text,
@@ -146,6 +154,10 @@ class GFX_EXPORT Canvas {
   // Obsolete version.  Use the above version which takes FontList.
   static int GetStringWidth(const base::string16& text, const Font& font);
 
+  // This is same as GetStringWidth except that fractional width is returned.
+  static float GetStringWidthF(const base::string16& text,
+                               const FontList& font_list);
+
   // Returns the default text alignment to be used when drawing text on a
   // Canvas based on the directionality of the system locale language.
   // This function is used by Canvas::DrawStringInt when the text alignment