PlatformFontWin::DeriveFontWithHeight insensitive to base font's height

ui/gfx/platform_font_win_unittest.cc

Index: ui/gfx/platform_font_win_unittest.cc
diff --git a/ui/gfx/platform_font_win_unittest.cc b/ui/gfx/platform_font_win_unittest.cc
index 1ecdde1d352db9d7b25e5a6c3ee62be48d79ca0a..67446ebc39e3cb2fa828a76f3f48fadfc0b83129 100644
--- a/ui/gfx/platform_font_win_unittest.cc
+++ b/ui/gfx/platform_font_win_unittest.cc
@@ -67,6 +67,23 @@ TEST(PlatformFontWinTest, DeriveFontWithHeight) {
     EXPECT_EQ(expected_font.GetFontSize(), rederived_font.GetFontSize());
     EXPECT_EQ(expected_font.GetHeight(), rederived_font.GetHeight());
   }
+
+  const Font bigger_font(base_font.GetFontName(), base_font.GetFontSize() + 10);

[Alexei Svitkine (slow), 2014/05/09 21:21:00]

Oops, I see you already added a test.

Can you make it a separate test case?

A good convention to use is to add a _ and suffix after the name of the method,
so it could be something like:

DeriveFontWithHeight_Consistency

[Tomasz Moniuszko, 2014/05/29 10:46:40]

Done.

+  PlatformFontWin* bigger_platform_font =
+      static_cast<PlatformFontWin*>(bigger_font.platform_font());
+
+  int requested_height = (base_font.GetHeight() + bigger_font.GetHeight()) / 2;

[Alexei Svitkine (slow), 2014/05/09 21:21:00]

Is it possible to do something more straight forward like your email example?
(i.e. with hardcoded heights), rather than this kind of more complicated
calculation?

[Tomasz Moniuszko, 2014/05/29 10:46:40]

Done.

+  ASSERT_GT(requested_height, base_font.GetHeight());
+  ASSERT_LT(requested_height, bigger_font.GetHeight());
+
+  Font derived_font_1 =
+      platform_font->DeriveFontWithHeight(requested_height, 0);
+  Font derived_font_2 =
+      bigger_platform_font->DeriveFontWithHeight(requested_height, 0);
+
+  // Derived fonts should be the same height for both higher and lower base
+  // fonts.
+  EXPECT_EQ(derived_font_1.GetHeight(), derived_font_2.GetHeight());
 }
 
 // Callback function used by DeriveFontWithHeight_MinSize() below.