Update the chrome PDF extension to use the modified streams API

BUG=303491
R=zork@chromium.org
TBR=arv@chromium.org

Review URL: https://codereview.chromium.org/181503008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@253660 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 253660