DevTools: WebSocketFrameView: fix UI.

UI is broken, because SplitView componentisation reduced CSS visibility.

BUG=436571

Review URL: https://codereview.chromium.org/756293003

git-svn-id: svn://svn.chromium.org/blink/trunk@186107 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: status bar titles are missing.

BUG=437166

Review URL: https://codereview.chromium.org/765713002

git-svn-id: svn://svn.chromium.org/blink/trunk@186108 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: allow moving views between SplitViews.

Review URL: https://codereview.chromium.org/766683003

git-svn-id: svn://svn.chromium.org/blink/trunk@186109 bbb929c8-8fbe-4397-9dbb-9b2b20218538