[Objective-C] Support a new special module flag.

"Objective-C Class Properties" will be put into the objc_imageinfo struct.

rdar://23891898

llvm-svn: 259270

llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp

@@ -467,6 +467,7 @@ emitModuleFlags(MCStreamer &Streamer,
     } else if (Key == "Objective-C Garbage Collection" ||
                Key == "Objective-C GC Only" ||
                Key == "Objective-C Is Simulated" ||
+               Key == "Objective-C Class Properties" ||
                Key == "Objective-C Image Swift Version") {
       ImageInfoFlags |= mdconst::extract<ConstantInt>(Val)->getZExtValue();
     } else if (Key == "Objective-C Image Info Section") {