Revert "Enable and update app_management_view/main_view_test.js"

This reverts commit 0defc950.

Reason for revert: Causes failure (crash) on linux-chromeos-dbg

https://ci.chromium.org/ui/p/chromium/builders/ci/linux-chromeos-dbg/22474/steps?succeeded=true&debug=false

Original change's description:
> Enable and update app_management_view/main_view_test.js
>
> main_view_test was disabled and out of date with the latest
> iteration of main_view_test. One out of date test is removed
> and another is updated to reflect recent changes.
>
> This is done to prepare for Polymer 3 migration.
>
> Bug: 1045266
> Change-Id: Ic5855d0df4ce50aef6c48f613fce20b342723229
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2653659


> Commit-Queue: Claude van der Merwe <cvandermerwe@google.com>
> Reviewed-by: Jeevan Shikaram <jshikaram@chromium.org>
> Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#850266}

TBR=khorimoto@chromium.org,jshikaram@chromium.org,chromium-scoped@luci-project-accounts.iam.gserviceaccount.com,cvandermerwe@google.com

Change-Id: If23d4b0c2b21804f2a7a21062e21cfe9f728fbc9
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1045266
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2673529


Reviewed-by: Anders Hartvoll Ruud <andruud@chromium.org>
Commit-Queue: Anders Hartvoll Ruud <andruud@chromium.org>
Cr-Commit-Position: refs/heads/master@{#850533}