Reproduction steps:
1. Create a new project.
2. Build it for iOS.
3. Wait until memory usage increase starts to stall.
3. Compare memory usage between versions 2017.3.0a1 and 2017.3.0b1.
- Tested with Xcode using Debug navigator and Editor profiler.

Actual behavior:
2017.3.0a1 - 37.6 mb
2017.3.0b1 - 44 mb

Expected behavior:
2017.3.0a1 - 37.6 mb
2017.3.0b1 ~ 37.6 mb

Reproduced with:
iOS
2017.3.0b1, 2017.3.1p2

Not reproducible with:
2017.3.0a1

Note:
Results may vary between devices.

Fixed:
2018.1.0b9 - 41.2 mb