icu: Add defines for Fuchsia

source/common/unicode/platform.h

Index: source/common/unicode/platform.h
diff --git a/source/common/unicode/platform.h b/source/common/unicode/platform.h
index 057182d31da22cf0494c0f679670d15bb932febc..5e46903ac29286cfc6bfc4fea534714589c9ea32 100644
--- a/source/common/unicode/platform.h
+++ b/source/common/unicode/platform.h
@@ -132,6 +132,8 @@
 #define U_PF_BROWSER_NATIVE_CLIENT 4020
 /** Android is based on Linux. @internal */
 #define U_PF_ANDROID 4050
+/** Fuchsia is a POSIX-ish platform. @internal */
+#define U_PF_FUCHSIA 4100
 /* Maximum value for Linux-based platform is 4499 */
 /** z/OS is the successor to OS/390 which was the successor to MVS. @internal */
 #define U_PF_OS390 9000
@@ -152,6 +154,8 @@
 #   include <android/api-level.h>
 #elif defined(__pnacl__) || defined(__native_client__)
 #   define U_PLATFORM U_PF_BROWSER_NATIVE_CLIENT
+#elif defined(__Fuchsia__)
+#   define U_PLATFORM U_PF_FUCHSIA
 #elif defined(linux) || defined(__linux__) || defined(__linux)
 #   define U_PLATFORM U_PF_LINUX
 #elif defined(__APPLE__) && defined(__MACH__)