Uses and returns the fractional width in text eliding

ui/gfx/font_unittest.cc

 // Copyright (c) 2012 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.
 
 #include "ui/gfx/font.h"
 
 #include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 125 matching lines @@
 TEST_F(FontTest, DeriveFontKeepsOriginalSizeIfHeightOk) {
   Font cf("Arial", 8);
   // The minimum font size is set to 5 in browser_main.cc.
   ScopedMinimumFontSizeCallback minimum_size(5);
 
   Font derived_font = cf.DeriveFont(-2);
   EXPECT_EQ(6, derived_font.GetFontSize());
 }
 #endif  // defined(OS_WIN)
 
+#if defined(OS_MACOSX)
+TEST_F(FontTest, FractionalWidth) {
+  Font cf("Arial", 16);
+
+  float width = cf.GetAverageCharacterWidth();
+  EXPECT_GT(width - static_cast<int>(width), 0);
+
+  width = cf.GetExpectedTextWidth(1);
+  EXPECT_GT(width - static_cast<int>(width), 0);
+
+  width = cf.GetStringWidth(ASCIIToUTF16("This is a test"));
+  EXPECT_GT(width - static_cast<int>(width), 0);
+}
+#endif
+
 }  // namespace
 }  // namespace gfx