Rebaseline after https://codereview.chromium.org/13778003

TBR=tasak
BUG=226048

Review URL: https://codereview.chromium.org/14049012

git-svn-id: svn://svn.chromium.org/blink/trunk@148379 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Enable toolbar customization.

Allow add/remove selected set of tools on the toolbar. The new
behavior is put behind an experiment.

BUG=229418
R=pfeldman@chromium.org
NOTRY=true

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=148285

Review URL: https://codereview.chromium.org/13818009

git-svn-id: svn://svn.chromium.org/blink/trunk@148380 bbb929c8-8fbe-4397-9dbb-9b2b20218538