Remove incompatible Unicode compatibility types.

As well intentioned as these were, uint16_t and C++11's char16_t are
_not_ actually compatible. They are not implicitly convertible, and
they mangle differently, so they are not even ABI compatible. In our
now wonderous world of C++11, no one should be using these, so just
kill them.

Bug: 18300613
Change-Id: I06d92d7f1d937dd94a620874323d4c50eb6a31bd

include/utils/Unicode.h

@@ -22,12 +22,6 @@
 
 extern "C" {
 
-// Definitions exist in C++11
-#if defined __cplusplus && __cplusplus < 201103L
-typedef unsigned int   char32_t;
-typedef unsigned short char16_t;
-#endif
-
 // Standard string functions on char16_t strings.
 int strcmp16(const char16_t *, const char16_t *);
 int strncmp16(const char16_t *s1, const char16_t *s2, size_t n);