Use the current download directory when installing extensions.
Use the current download directory when installing extensions.

The WebstoreInstaller had been downloading extensions to the default download directory, rather than the user's current selection.

BUG=109468
TEST=manual


Review URL: http://codereview.chromium.org/9151004

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@116961 0039d316-1c4b-4281-b951-d872f2087c98

ropik/chromium,ropik/chromium,gavinp/chromium,adobe/chromium,gavinp/chromium,ropik/chromium,yitian134/chromium,adobe/chromium,yitian134/chromium,gavinp/chromium,ropik/chromium,yitian134/chromium,gavinp/chromium,yitian134/chromium,ropik/chromium,adobe/chromium,gavinp/chromium,ropik/chromium,adobe/chromium,gavinp/chromium,adobe/chromium,yitian134/chromium,gavinp/chromium,ropik/chromium,gavinp/chromium,adobe/chromium,yitian134/chromium,ropik/chromium,adobe/chromium,yitian134/chromium,adobe/chromium,yitian134/chromium,adobe/chromium,ropik/chromium,gavinp/chromium,gavinp/chromium,adobe/chromium,adobe/chromium,yitian134/chromium,yitian134/chromium