Don't hang if can't downsize font.

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 9502875f3a7e89ab9b609ed1e06ccfaffb4bb9f6..bfbe92203d1a6ccb02a1d2cd17c49415d3474729 100644
--- a/ui/gfx/platform_font_win_unittest.cc
+++ b/ui/gfx/platform_font_win_unittest.cc
@@ -92,4 +92,13 @@ TEST(PlatformFontWinTest, DeriveFontWithHeight_MinSize) {
   PlatformFontWin::get_minimum_font_size_callback = old_callback;
 }
 
+TEST(PlatformFontWinTest, DeriveFontWithHeight_TooSmall) {
+  const Font base_font;
+  PlatformFontWin* platform_font =
+      static_cast<PlatformFontWin*>(base_font.platform_font());
+
+  const Font derived_font = platform_font->DeriveFontWithHeight(1, 0);
+  EXPECT_GT(derived_font.GetHeight(), 1);
+}
+
 }  // namespace gfx