[noinline attribute] add noinline attribute.

Propagate it to SILFunction and use it in PerformanceInliner. We also serialize
and parse the attribute.

rdar://15882816


Swift SVN r19150

lib/SILPasses/GenericSpecializer.cpp

@@ -92,7 +92,7 @@ SILFunction *SpecializingCloner::initCloned(SILFunction *Orig,
     SILFunction::create(M, getSpecializedLinkage(Orig->getLinkage()),
                         NewName, FTy, nullptr,
                         Orig->getLocation(), Orig->isBare(),
-                        Orig->isTransparent(), 0,
+                        Orig->isTransparent(), Orig->isNoinline(), 0,
                         Orig->getDebugScope(), Orig->getDeclContext());
 
   NumSpecialized++;