MediaStream API: Updating NavigatorUserMediaError
Updating NavigatorUserMediaError both to reflect the latest spec but also
to make it a bit cleaner.

This patch has been committed as r157697 and rolled out as r157752 due to
failing browser_tests. The tests have now been updated to accept both the
new and the old error name.

BUG=294145

Review URL: https://chromiumcodereview.appspot.com/24541002

git-svn-id: svn://svn.chromium.org/blink/trunk@158527 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[DevTools] Enable deleting of a snippet by pressing delete key

This patch enables deleting a snippet by pressing delete key.
Currently to delete a snippet one has to right click and
click on 'Remove' option of the context menu.

R=pfeldman

Review URL: https://chromiumcodereview.appspot.com/25029002

git-svn-id: svn://svn.chromium.org/blink/trunk@158528 bbb929c8-8fbe-4397-9dbb-9b2b20218538