Change the streamlined hosted app creation buttons text to "Add shortcut to this website"

This CL changes the string in the streamlined hosted app creation button
in order to be less inconsistent with the actual dialog which appears
with the title "Add shortcut".

BUG=318607

Review URL: https://codereview.chromium.org/183253005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255585 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 255585
Roll trace-viewer to r1203

TBR=dsinclair
NOTRY=True

Review URL: https://codereview.chromium.org/189483003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255586 0039d316-1c4b-4281-b951-d872f2087c98
Update .DEPS.git

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255587 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 255587