Removing memory object checks based on "dumpsys meminfo"

This "dumpsys meminfo" can return phantom references that we have no control over and that can break all counting.

Given that the removed code haven't found issues in the past, and that we have Launcher activity counting implemented via TestProtocol.REQUEST_GET_ACTIVITIES, removing all "dumpsys meminfo" code.

Test: presubmit
Bug: 260260325
Flag: N/A
Change-Id: Ic80a6145d76d7cddfedad5328cb141a955b1eaf5