[ownership] Move ownership lowering past SROA.

[gottesmm]

I already updated SROA for this and we already have tests/etc. We have just been
waiting on some other passes to be moved afterwards.

[gottesmm]

@swift-ci test

[gottesmm]

@swift-ci benchmark

[gottesmm]

Windows failure is I believe an lldb failure. Not this.

[swift-ci]

Performance: -O

Code size: -O

Performance: -Osize

Improvement	OLD	NEW	DELTA	RATIO
FlattenListFlatMap	6064	3944	-35.0%	1.54x (?)
FlattenListLoop	2060	1628	-21.0%	1.27x (?)
DictionaryKeysContainsNative	31	28	-9.7%	1.11x (?)

Code size: -Osize

Performance: -Onone

Regression	OLD	NEW	DELTA	RATIO
StringToDataMedium	7100	7850	+10.6%	0.90x (?)

Code size: -swiftlibs

How to read the data

The tables contain differences in performance which are larger than 8% and differences in code size which are larger than 1%.

If you see any unexpected regressions, you should consider fixing the
regressions before you merge the PR.

Noise: Sometimes the performance results (not code size!) contain false
alarms. Unexpected regressions which are marked with '(?)' are probably noise.
If you see regressions which you cannot explain you can try to run the
benchmarks again. If regressions still show up, please consult with the
performance team (@eeckstein).

Hardware Overview

  Model Name: Mac Pro
  Model Identifier: MacPro6,1
  Processor Name: 12-Core Intel Xeon E5
  Processor Speed: 2.7 GHz
  Number of Processors: 1
  Total Number of Cores: 12
  L2 Cache (per Core): 256 KB
  L3 Cache: 30 MB
  Memory: 64 GB

[meg-gupta]

lgtm