DevTools: Show colors with alpha in the color picker

R=pfeldman, vsevik
BUG=251697

Review URL: https://chromiumcodereview.appspot.com/17648009

git-svn-id: svn://svn.chromium.org/blink/trunk@153008 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Adjust distance from Window metrics in heap snapshot.

Make user root objects to have distance from user root objects of zero.
Make snapshot meta root (that is invisible) to have a virtual distance of -1,
so its children have distance of 0.

BUG=
R=loislo@chromium.org

Review URL: https://codereview.chromium.org/17680004

git-svn-id: svn://svn.chromium.org/blink/trunk@153009 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Sources panel search should start incrementally even with a single character query.

R=pfeldman@chromium.org

Review URL: https://codereview.chromium.org/17582019

git-svn-id: svn://svn.chromium.org/blink/trunk@153010 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Mark SVG{Circle,Path,Rect}Element::createRenderer() as virtual.

While not strictly required in these cases, the missing keyword is inconsistent and misleading.

R=schenney@chromium.org,pdr@chromium.org

Review URL: https://chromiumcodereview.appspot.com/17680005

git-svn-id: svn://svn.chromium.org/blink/trunk@153011 bbb929c8-8fbe-4397-9dbb-9b2b20218538