content: A couple of device-scale-factor fixes:

 * Implement WebWidgetClient::deviceScaleFactor
 * Set the device-scale-factor on WebView.

BUG=127795
TEST=manually

Review URL: https://chromiumcodereview.appspot.com/10481005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@140801 0039d316-1c4b-4281-b951-d872f2087c98
3 files changed