[PATCH] Update __dfsw_s{, n}printf custom functions for new calling convention.

[Lorenzo Martignoni]

LGTM

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Comment at: lib/dfsan/dfsan_custom.cc:1067
@@ -1073,3 +1066,3 @@
     const Chunk& chunk = chunks[i];
 
     switch (chunk.label_type) {
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The labelling could now be in principle performed right after the formatting. I agree that this can be done later since not urgent. Maybe add a 'TODO(martignlo): ....'?

http://reviews.llvm.org/D6029