[automerger skipped] Modernize codebase by replacing NULL with nullptr am: 5f765b86ae  -s ours am: 62a94ada3b  -s ours am: 42cc18fc02  -s ours
am: 064bdb5754  -s ours

Change-Id: I1d1952a8f40af22cc4e1d8c751516f20e518aa5e