Removed checking for template URL specialization in TopSites.

When asked to do |prefix_match|, TopSitesImpl::GetPageThumbnail no longer uses URL specialization (eg. appending path suffixes) since it caused bad thumbnails to be shown in some cases.

BUG=

Review URL: https://codereview.chromium.org/61763006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233617 0039d316-1c4b-4281-b951-d872f2087c98
Adding Linux App Launcher.

This only works in Linux Aura builds. There is currently no way to
launch the App Launcher besides running: chrome --show-app-list.

BUG=299250

Review URL: https://codereview.chromium.org/63033005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233618 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 233617
SVN changes up to revision 233618