[Predef-contribute] add Android to the list of Operating Systems

[Hans-Christoph S. <ha...@gu...>]

Thanks for this reference, it is very useful.  It is missing Android,
that macro is __ANDROID__.  It is hardcoded into the Android
cross-compiler (Android NDK) provided by Google:

hans@palatschinken ~ $ find
/usr/local/android-ndk/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/
-type f | xargs grep ANDROID
Binary file
/usr/local/android-ndk/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/libexec/gcc/arm-linux-androideabi/4.4.3/cc1
matches
Binary file
/usr/local/android-ndk/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/libexec/gcc/arm-linux-androideabi/4.4.3/cc1plus
matches
hans@palatschinken ~ $ strings
/usr/local/android-ndk/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/libexec/gcc/arm-linux-androideabi/4.4.3/cc1
| grep ANDROID
__ANDROID__
hans@palatschinken ~ $ strings
/usr/local/android-ndk/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/libexec/gcc/arm-linux-androideabi/4.4.3/cc1plus
| grep ANDROID
__ANDROID__


.hc