Revert 228211 "Move renderer plugin code into a new component."
There is an error in the ChromePluginPlaceholder destructor
causing pointers to it to be left around after it is freed.
Fix will follow, but reverting for now.
BUG=306815,306803
> Move renderer plugin code into a new component.
>
> Android Webview needs to use some of the renderer plugin code, however
> this code is currently in chrome. This commit moves the parts of this
> code that don't depend on the rest of chrome into a new component.
>
> BUG=283713
>
> Review URL: https://codereview.chromium.org/
23606022
TBR=aberent@chromium.org
Review URL: https://codereview.chromium.org/
26781004
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228456 0039d316-1c4b-4281-b951-d872f2087c98