Merging r182166:

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r182166 | mkopec | 2013-05-17 15:21:08 -0700 (Fri, 17 May 2013) | 3 lines

The Linux process plugin wasn't returning the correct linux signals. This fixes that.
Thus, this patch also negates a previous fix for handling SIGCHLD.

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llvm-svn: 182518