Fix JNI generation on Darwin and XCode 5.1
Fix JNI generation on Darwin and XCode 5.1

clang now errors out if an unknown argument is used:
$ cpp -fpreprocessed
clang: error: unknown argument: '-fpreprocessed' [-Wunused-command-line-argument-hard-error-in-future]
clang: note: this will be a hard error (cannot be downgraded to a warning) in the future

This is ugly but works...

Change-Id: I47d91f132f6222413147807ffd2ac5bcc4256896

scotthartbti/android_external_chromium_org,VanirAOSP/external_chromium_org,Epirex/android_external_chromium_org,TEAM-Gummy/platform_external_chromium_org,TEAM-Gummy/platform_external_chromium_org,MyAOSP/external_chromium_org,temasek/android_external_chromium_org,temasek/android_external_chromium_org,scotthartbti/android_external_chromium_org,mkaluza/external_chromium_org,mkaluza/external_chromium_org,ChronoMonochrome/android_external_chromium_org,VanirAOSP/external_chromium_org,MyAOSP/external_chromium_org,MyAOSP/external_chromium_org,ChronoMonochrome/android_external_chromium_org,scotthartbti/android_external_chromium_org,TEAM-Gummy/platform_external_chromium_org,ThirdProject/android_external_chromium_org,mkaluza/external_chromium_org,ThirdProject/android_external_chromium_org,androidarmv6/android_external_chromium_org,katstalk/android_external_chromium_org,temasek/android_external_chromium_org,ThirdProject/android_external_chromium_org,ThirdProject/android_external_chromium_org,Epirex/android_external_chromium_org,scotthartbti/android_external_chromium_org,ChronoMonochrome/android_external_chromium_org,Epirex/android_external_chromium_org,VanirAOSP/external_chromium_org,mkaluza/external_chromium_org,scotthartbti/android_external_chromium_org,mkaluza/external_chromium_org,TEAM-Gummy/platform_external_chromium_org,scotthartbti/android_external_chromium_org,scotthartbti/android_external_chromium_org,temasek/android_external_chromium_org,TEAM-Gummy/platform_external_chromium_org,MyAOSP/external_chromium_org,TEAM-Gummy/platform_external_chromium_org,ChronoMonochrome/android_external_chromium_org,MyAOSP/external_chromium_org,katstalk/android_external_chromium_org,katstalk/android_external_chromium_org,androidarmv6/android_external_chromium_org,katstalk/android_external_chromium_org,ChronoMonochrome/android_external_chromium_org,temasek/android_external_chromium_org,Epirex/android_external_chromium_org,VanirAOSP/external_chromium_org,ChronoMonochrome/android_external_chromium_org,mkaluza/external_chromium_org,TEAM-Gummy/platform_external_chromium_org,androidarmv6/android_external_chromium_org,androidarmv6/android_external_chromium_org,MyAOSP/external_chromium_org,mkaluza/external_chromium_org,mkaluza/external_chromium_org,ThirdProject/android_external_chromium_org,ChronoMonochrome/android_external_chromium_org,mkaluza/external_chromium_org,ChronoMonochrome/android_external_chromium_org,ChronoMonochrome/android_external_chromium_org,TEAM-Gummy/platform_external_chromium_org,ThirdProject/android_external_chromium_org,temasek/android_external_chromium_org,androidarmv6/android_external_chromium_org,scotthartbti/android_external_chromium_org,katstalk/android_external_chromium_org,androidarmv6/android_external_chromium_org,Epirex/android_external_chromium_org,Epirex/android_external_chromium_org,temasek/android_external_chromium_org,ThirdProject/android_external_chromium_org,katstalk/android_external_chromium_org,MyAOSP/external_chromium_org,Epirex/android_external_chromium_org,VanirAOSP/external_chromium_org,temasek/android_external_chromium_org,ThirdProject/android_external_chromium_org,Epirex/android_external_chromium_org,katstalk/android_external_chromium_org,VanirAOSP/external_chromium_org,VanirAOSP/external_chromium_org,androidarmv6/android_external_chromium_org,ThirdProject/android_external_chromium_org,VanirAOSP/external_chromium_org,katstalk/android_external_chromium_org,katstalk/android_external_chromium_org,androidarmv6/android_external_chromium_org,TEAM-Gummy/platform_external_chromium_org,MyAOSP/external_chromium_org,MyAOSP/external_chromium_org