Bug 1460858 - Fix serialization/deserialization of SlantStyle for the Android startupCache, to ensure proper styled face selection. r=jwatt

gfx/src/FontPropertyTypes.h

@@ -347,8 +347,9 @@ public:
         return Oblique(angle);
       }
       // Not recognized as an oblique angle; maybe it's from a startup-cache
-      // created by an older version. Just treat it as 'normal'.      
-      return Normal();
+      // created by an older version. The style field there used a simple 0/1
+      // for normal/italic respectively.
+      return aString[0] == '0' ? Normal() : Italic();
     }
   }
 

gfx/thebes/gfxFT2FontList.cpp

@@ -1060,7 +1060,11 @@ AppendToFaceList(nsCString& aFaceList,
     aFaceList.Append(',');
     aFaceList.AppendInt(aFontEntry->mFTFontIndex);
     aFaceList.Append(',');
-    aFaceList.Append(aFontEntry->IsItalic() ? '1' : '0');
+    // Note that ToString() appends to the destination string without
+    // replacing existing contents (see FontPropertyTypes.h)
+    aFontEntry->SlantStyle().Min().ToString(aFaceList);
+    aFaceList.Append(':');
+    aFontEntry->SlantStyle().Max().ToString(aFaceList);
     aFaceList.Append(',');
     aFaceList.AppendFloat(aFontEntry->Weight().Min().ToFloat());
     aFaceList.Append(':');