Use the NativeTheme to create the text color for text during the generated card animation.

Also adjust the background so that darker colors are lighter and by a larger amount if really dark.

BUG=320899

Review URL: https://codereview.chromium.org/107623002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244083 0039d316-1c4b-4281-b951-d872f2087c98
Blink roll 164685:164830

http://build.chromium.org/f/chromium/perf/dashboard/ui/changelog_blink.html?url=/trunk&range=164686:164830&mode=html
TBR=fsamuel@chromium.org

Review URL: https://codereview.chromium.org/133163002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244084 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 244084