Linux: fix double italic on some fonts.

skia/ext/SkFontHost_fontconfig_direct.cpp

Index: skia/ext/SkFontHost_fontconfig_direct.cpp
diff --git a/skia/ext/SkFontHost_fontconfig_direct.cpp b/skia/ext/SkFontHost_fontconfig_direct.cpp
index dc20afffc51c6b4b98215e3073ad8c2e7bd9f9ff..8c89d551e9bf4e9b7de9980e06d322ac942eb4ec 100644
--- a/skia/ext/SkFontHost_fontconfig_direct.cpp
+++ b/skia/ext/SkFontHost_fontconfig_direct.cpp
@@ -179,10 +179,17 @@ bool FontConfigDirect::Match(std::string* result_family,
     if (FcPatternGetInteger(match, FC_SLANT, 0, &resulting_italic))
       resulting_italic = FC_SLANT_ROMAN;
 
+    // If we ask for an italic font, fontconfig might take a roman font and set
+    // the undocumented property FC_MATRIX to a skew matrix. It'll then say
+    // that the font is italic or oblique. So, if we see a matrix, we don't
+    // believe that it's italic.
+    FcValue matrix;
+    const bool have_matrix = FcPatternGet(match, FC_MATRIX, 0, &matrix) == 0;
+
     if (is_bold)
       *is_bold = resulting_bold >= FC_WEIGHT_BOLD;
     if (is_italic)
-      *is_italic = resulting_italic == FC_SLANT_ITALIC;
+      *is_italic = resulting_italic > FC_SLANT_ROMAN && !have_matrix;
 
     if (result_family)
         *result_family = (char *) c_family;