Read memory stats from /proc/pid/stat file.

(cherry pick from commit 0301683e49ab255769b15469487feaab3466167a)
Bug: 117333340
Test: Manual testing using alloc-stress tool
Merged-In: Ie555933aafa6a6b7aa1dbf5518ebe804376e0afd

Change-Id: I8ab08606dba7de2f65711204453067dbfbdcbdd8
2 files changed