When we try to render to "temporary render texture" using CommandBuffer and MSAA is enabled, the depth is not preserved.

Reproduction steps:
1. Open attached project (MSAADepth.zip)
2. Open Test scene (Make sure anti aliasing is not disabled)
3. Hit play

Expected result:
Half of red sphere is visible on black background (See attached image)

Actual result:
Only black bacground is visible (on Unity older than 5.6.0a1 console is also spammed with following error:
"depthSurface == NULL || rcolorZero->backBuffer == depthSurface->backBuffer" )

Reproduced with errors:
Unity 5.2.5f1, 5.3.3f1, 5.4.2f1, 5.4.2p3, 5.5.0b11

Reproduced but without errors:
5.6.0a1, 5.6.0a2