Fix linking issues in external/skia because of missing implementation.

The skia library uses FT_Library_SetLcdFilter(...), to see if LCD
text is supported on the platform.  Android currently does not
implement LCD text, but we should not fail to link. Rather we should
return the appropriate error code.

Change-Id: Ib04bee1be2f3a66c7babea28442884492ddc1c83
diff --git a/Android.mk b/Android.mk
index 4581c89..8db5eb2 100644
--- a/Android.mk
+++ b/Android.mk
@@ -17,6 +17,7 @@
 	src/base/ftbbox.c \
 	src/base/ftbitmap.c \
 	src/base/ftglyph.c \
+	src/base/ftlcdfil.c \
 	src/base/ftstroke.c \
 	src/base/ftxf86.c \
 	src/base/ftbase.c \