Reland "[network] Show memory inspector in the "Response" tab for binary content"

This is a reland of commit f233d985e4f591e678749c6350fcaabb8b084794

The reland fixes the flaky unit test by showing the widget.
This causes the detach to actually remove the LMI viewer from the
DOM and to unregister the resize observer.

Original change's description:
> [network] Show memory inspector in the "Response" tab for binary content
>
> This CL changes the Network > Response tab to show the linear memory
> inspector for network requests with a binary payload instead of nothing.
>
> Until recently we would blindly decode binary content in some cases
> (but not all). This only made sense if the binary content actually
> had some valid ascii sequences in it's content as the rest would be
> garbage.
>
> This CL restores the ability to inspect binary content, but via the
> linear memory inspector which produces a hexdump of the content.
> This allows developers to still check ascii sequences in binary
> content and even check the binary data directly.
>
> R=kimanh@chromium.org
>
> Fixed: 372158884
> Change-Id: Ifdac1607b767a1522343e9e9bfc161a0e5d2ffc3
> Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/5917828
> Reviewed-by: Kim-Anh Tran <kimanh@chromium.org>
> Commit-Queue: Simon Zünd <szuend@chromium.org>

Fixed: 372158884
Change-Id: I51db1cba7987b8ee8173535584802a9aa0f4d1a8
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/5920345
Commit-Queue: Kim-Anh Tran <kimanh@chromium.org>
Auto-Submit: Simon Zünd <szuend@chromium.org>
Reviewed-by: Kim-Anh Tran <kimanh@chromium.org>