Revert of content-shell: Allow running content-shell headless with --dump-render-tree. (https://codereview.chromium.org/145253002/)

Reason for revert:
Crashes a lot on linux_rel during layout tests

Original issue's description:
> content-shell: Allow running content-shell headless with --dump-render-tree.
> 
> Do some refactoring to allow using ShellAuraPlatformData in aura content_shell
> (with or without views). ShellAuraPlatformData is used for non-views aura
> content_shell (e.g. ozone) for all purposes, and in views content_shell only for
> headless mode.
> 
> BUG=316712
> R=jam@chromium.org, sky@chromium.org
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=246921

TBR=dpranke@chromium.org,varkha@chromium.org,r.kasibhatla@samsung.com,jam@chromium.org,sky@chromium.org,sadrul@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=316712

Review URL: https://codereview.chromium.org/147773002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@247148 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 247148