Enable profile pinning by setting browser window relaunch details

Make it possible to pin shortcuts by setting the relaunch data for each browser window.

BUG=177490,107080,146647
TEST=Create separate profiles and pin the taskbar icons. Clicking the pinned icons should relaunch chrome with the appropriate profile.

TBR=cpu@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=231295

Review URL: https://codereview.chromium.org/14122006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@232109 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 232109