DevTools: [Settings] Use SELECT instead of radiobuttons for the color format

R=pfeldman, vsevik, yurys@chromium.org
BUG=235690

Review URL: https://chromiumcodereview.appspot.com/18182018

git-svn-id: svn://svn.chromium.org/blink/trunk@154093 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Element's insertAdjacent API should lazy attach

insertAdjacentElement, insertAdjacentText and insertAdjacentHTML should all lazyAttach
just like appendChild() would have.

I also removed some redundant ASSERT_WITH_SECURITY_IMPLICATIONS that aren't needed
since we use toElement() right below them which contains the same assert.

R=ojan@chromium.org

Review URL: https://codereview.chromium.org/19045003

git-svn-id: svn://svn.chromium.org/blink/trunk@154094 bbb929c8-8fbe-4397-9dbb-9b2b20218538