Implement <iconv.h>.

Bug: http://b/32978596
Test: ran tests
Change-Id: I56b6ae3d9c5a3a56d2b4afba33fb8f9e964bf7b9
diff --git a/libc/private/icu.h b/libc/private/icu.h
index ae253fa..a671e98 100644
--- a/libc/private/icu.h
+++ b/libc/private/icu.h
@@ -33,6 +33,9 @@
 #include <wchar.h>
 
 typedef int8_t UBool;
+#define FALSE 0
+#define TRUE 1
+
 typedef int32_t UChar32;
 
 enum UProperty {