Merging r155285:

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r155285 | chapuni | 2012-04-21 07:51:02 -0700 (Sat, 21 Apr 2012) | 1 line

CMake: Enable LLVM_COMPILER_JOBS on all MS IDEs. We don't support older environments than VS9.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_31@155335 91177308-0d34-0410-b5e6-96231b3b80d8