Revert "Minimal zoom implementation".

Per the design meeting, we are abandoning this feature for now - there is not enough time to ensure it is of acceptable quality.

This reverts commit 4329d453ecf4eaef6aba2b3744fa571ab1e1647e.

Change-Id: I27c113ffecb617d442557163722ea5181ed0b2f4
Merge "Revert "Minimal zoom implementation"."