Disable shrinksStandaloneImagesToFit on Android

The shrinksStandaloneImagesToFit feature isn't suitable on Android.
Instead we use viewport meta tag to let the image fit width (already in
ImageDocument.cpp in blink).

BUG=246395

Review URL: https://codereview.chromium.org/27036007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228758 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 228758