DevTools: Support replacing with regex capturing groups in editor

BUG=382216
R=lushnikov

Review URL: https://codereview.chromium.org/664143002

git-svn-id: svn://svn.chromium.org/blink/trunk@184084 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[DevTools] Make all parameters of Tracing.start optional.

BUG=405566

Review URL: https://codereview.chromium.org/665123008

git-svn-id: svn://svn.chromium.org/blink/trunk@184088 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Embed modular CSS into concatenated module JS

R=pfeldman

Review URL: https://codereview.chromium.org/650613004

git-svn-id: svn://svn.chromium.org/blink/trunk@184090 bbb929c8-8fbe-4397-9dbb-9b2b20218538