linux/chromeos: Improve querying for Fontconfig defaults.

ui/gfx/font_render_params_linux_unittest.cc

Index: ui/gfx/font_render_params_linux_unittest.cc
diff --git a/ui/gfx/font_render_params_linux_unittest.cc b/ui/gfx/font_render_params_linux_unittest.cc
index 46a4fcfaac27f036693448205271b265cc92db1e..ee80e9be653c3c2673b2fa71583ec67649b24752 100644
--- a/ui/gfx/font_render_params_linux_unittest.cc
+++ b/ui/gfx/font_render_params_linux_unittest.cc
@@ -47,7 +47,8 @@ class TestFontDelegate : public LinuxFontDelegate {
 };
 
 // Loads the first system font defined by fontconfig_util_linux.h with a base
-// filename of |basename|. Case is ignored.
+// filename of |basename|. Case is ignored. FcFontMatch() requires there to be
+// at least one font present.
 bool LoadSystemFont(const std::string& basename) {
   for (size_t i = 0; i < kNumSystemFontsForFontconfig; ++i) {
     base::FilePath path(gfx::kSystemFontsForFontconfig[i]);
@@ -96,8 +97,11 @@ TEST_F(FontRenderParamsTest, Default) {
       CreateFontconfigEditStanza("hintstyle", "const", "hintslight") +
       CreateFontconfigEditStanza("rgba", "const", "rgb") +
       kFontconfigMatchFooter +
-      // Add a font match for Arial; it shouldn't be used when querying for
-      // default settings: http://crbug.com/421247
+      // Add a font match for Arial; it shouldn't be used on Chrome OS but when
+      // querying for default settings: http://crbug.com/421247
+      //
+      // The match _should_ take effect on desktop Linux, though:
+      // http://crbug.com/442443
       kFontconfigMatchFontHeader +
       CreateFontconfigTestStanza("family", "eq", "string", "Arial") +
       CreateFontconfigEditStanza("antialias", "bool", "true") +
@@ -110,9 +114,14 @@ TEST_F(FontRenderParamsTest, Default) {
   FontRenderParams params = GetFontRenderParams(
       FontRenderParamsQuery(true), NULL);
   EXPECT_TRUE(params.antialiasing);
-  EXPECT_TRUE(params.autohinter);
   EXPECT_TRUE(params.use_bitmaps);
+#if defined(OS_CHROMEOS)
+  EXPECT_TRUE(params.autohinter);
   EXPECT_EQ(FontRenderParams::HINTING_SLIGHT, params.hinting);
+#else
+  EXPECT_FALSE(params.autohinter);
+  EXPECT_EQ(FontRenderParams::HINTING_FULL, params.hinting);
+#endif
   EXPECT_FALSE(params.subpixel_positioning);
   EXPECT_EQ(FontRenderParams::SUBPIXEL_RENDERING_RGB,
             params.subpixel_rendering);
@@ -214,6 +223,7 @@ TEST_F(FontRenderParamsTest, Style) {
 }
 
 TEST_F(FontRenderParamsTest, Scalable) {
+  ASSERT_TRUE(LoadSystemFont("arial.ttf"));

[msw, 2014/12/18 01:10:49]

nit: We previously tried to avoid loading fonts for these tests wherever
possible. I realize it's needed for ForceFullHintingWhenAntialiasingIsDisabled,
but perhaps we should continue to avoid it here?

[Daniel Erat, 2014/12/18 17:17:59]

sure, done. just added it here since just about all of the other tests do it
now, but yeah, it doesn't seem to be necessary.

   // Load a config that only enables antialiasing for scalable fonts.
   ASSERT_TRUE(LoadConfigDataIntoFontconfig(temp_dir_.path(),
       std::string(kFontconfigFileHeader) +
@@ -256,6 +266,7 @@ TEST_F(FontRenderParamsTest, UseBitmaps) {
 }
 
 TEST_F(FontRenderParamsTest, ForceFullHintingWhenAntialiasingIsDisabled) {
+  ASSERT_TRUE(LoadSystemFont("arial.ttf"));
   // Load a config that disables antialiasing and hinting while requesting
   // subpixel rendering.
   ASSERT_TRUE(LoadConfigDataIntoFontconfig(temp_dir_.path(),