Removed trailing whitespace.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180696 91177308-0d34-0410-b5e6-96231b3b80d8
Added statistics to count the number of retains/releases before/after optimization.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180697 91177308-0d34-0410-b5e6-96231b3b80d8
[objc-arc] Apply the RV optimization to retains next to calls in ObjCARCContract instead of ObjCARCOpts.

Turning retains into retainRV calls disrupts the data flow analysis in
ObjCARCOpts. Thus we move it as late as we can by moving it into
ObjCARCContract.

We leave in the conversion from retainRV -> retain in ObjCARCOpt since
it enables the dataflow analysis.

rdar://10813093

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180698 91177308-0d34-0410-b5e6-96231b3b80d8