Enable SDCH support over HTTPS if --enable-sdch=2 switch is present.

BUG=313716

Review URL: https://codereview.chromium.org/123383002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243957 0039d316-1c4b-4281-b951-d872f2087c98
Make inline install for disabled items just re-enable them


Based on initial patch by rdevlin.cronin@chromium.org

BUG=308355

Review URL: https://codereview.chromium.org/130393002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243958 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 243958