Split ProcessRecord into separate cpp/h files am: e5522684a1 am: 20e1fd4a9d

Original change: https://android-review.googlesource.com/c/platform/system/memory/libmeminfo/+/2239335

Change-Id: I0691895a88230699493f5ca32b76e6dfea87346a
Signed-off-by: Automerger Merge Worker <[email protected]>