[Refactring] Turn HTMLImport::m_sync from bool to an enum.

This change introduces HTMLImport::SyncMode for readability.

TEST=none
BUG=356257
R=dominicc@chromium.org

Review URL: https://codereview.chromium.org/211363004

git-svn-id: svn://svn.chromium.org/blink/trunk@170067 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Make Array.remove O(N).

TEST=LayoutTests/inspector/utilities.html
R=alph, pfeldman

Review URL: https://codereview.chromium.org/212863005

git-svn-id: svn://svn.chromium.org/blink/trunk@170068 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Implement batch event forwarding from extension panels

Drive-by: Provide and handle a synthetic keyCode for synthetic KeyboardEvents.
This is required for handling of shortcuts forwarded from extension panels.

R=caseq

Review URL: https://codereview.chromium.org/212573006

git-svn-id: svn://svn.chromium.org/blink/trunk@170069 bbb929c8-8fbe-4397-9dbb-9b2b20218538