DevTools: press and hold should be changing color value in the spectrum.
DevTools: press and hold should be changing color value in the spectrum.

R=sergeyv
BUG=493551

Review URL: https://codereview.chromium.org/1220183003

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@198396 bbb929c8-8fbe-4397-9dbb-9b2b20218538

Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk