DevTools: [Shadow DOM] Introduce experimental Composed/Flattened Shadow DOM viewer.

BUG=392365

Review URL: https://codereview.chromium.org/826533002

git-svn-id: svn://svn.chromium.org/blink/trunk@187710 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: split FileSystemMapping into the actual FileSystemMapping and ExcludedFolderManager.

Review URL: https://codereview.chromium.org/825953002

git-svn-id: svn://svn.chromium.org/blink/trunk@187714 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: NetworkPanel: improve protocol detection.

BUG=444863

Review URL: https://codereview.chromium.org/820373002

git-svn-id: svn://svn.chromium.org/blink/trunk@187716 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: NetworkPanel: add negative text filters

BUG=444960

Review URL: https://codereview.chromium.org/823073002

git-svn-id: svn://svn.chromium.org/blink/trunk@187717 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: move setOverlayMessage from Debugger domain to Page

The overlay message makes sense for Page debugger only. Also it is not specific to debugger and we may decide to add more messages in the future so I've moved the command to Page domain.

BUG=439376

Review URL: https://codereview.chromium.org/801363004

git-svn-id: svn://svn.chromium.org/blink/trunk@187722 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: remove the UISourceCode.url getter, replace it with the networkURL accessor.

BUG=445179

Review URL: https://codereview.chromium.org/823353002

git-svn-id: svn://svn.chromium.org/blink/trunk@187724 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: initial support of FlowEvents in timeline

BUG=445053

Review URL: https://codereview.chromium.org/794073004

git-svn-id: svn://svn.chromium.org/blink/trunk@187725 bbb929c8-8fbe-4397-9dbb-9b2b20218538