Custom Element should have a wrapper while frame navigation

When frame navigation occurs, the script context containing
the custom element is destroyed. And, hence we were hitting
an early written.
This patch allocates the wrapper in whatever context the other
wrappers are being allocated in.

BUG=323430

Review URL: https://codereview.chromium.org/604773002

git-svn-id: svn://svn.chromium.org/blink/trunk@183064 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Credential Manager: Expose the runtime flag to the embedder.

The credential manager's current implementation exposes sensitive
information to websites via a JavaScript API. Until we have a good feel
for exactly what we want to expose, how we want to expose it, and what
UI needs to be tied to that exposure, we shouldn't enable this via the
general "Experimental Web Features" flag.

We do want to enable testing, though: creating a separate flag on
about:flags seems like a reasonable way of containing the risk.

BUG=400674

Review URL: https://codereview.chromium.org/617003006

git-svn-id: svn://svn.chromium.org/blink/trunk@183065 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[Blink-WebWorkers] WorkerSharedTimer cancels extra delayed tasks.

This CL has the Blink side changes to cancel extra delayed tasks posted
in WorkerSharedTimer. Previously extra tasks were being posted and allowed
to complete if multiple interval timers were scheduled on worker threads.
Now we will cancel any extra delayed task, made redundant due to newly scheduled
lesser timer interval tasks.

BUG=410786

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=182930

Review URL: https://codereview.chromium.org/563203002

git-svn-id: svn://svn.chromium.org/blink/trunk@183066 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Prepare to add a use counter for Intl.v8BreakIterator

BUG=

Review URL: https://codereview.chromium.org/621593003

git-svn-id: svn://svn.chromium.org/blink/trunk@183067 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: [CSS] do not include runtime-flag guarded properties in a supported list

As of today, we get all the properties from CSSProperties.in to generate
supported css properties. However, some of them are guarded by the runtime
flag. This patch avoids adding these properties to the front-end.

BUG=419326
R=apavlov

Review URL: https://codereview.chromium.org/619613008

git-svn-id: svn://svn.chromium.org/blink/trunk@183068 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Notify in console when an API fails because it needs to be invoked on user action.

This CL shows a console warning on requestFullScreen, requestPointerLock and
Notification.requestPermission api's, when they are not invoked on user action.

BUG=365779

Review URL: https://codereview.chromium.org/600773002

git-svn-id: svn://svn.chromium.org/blink/trunk@183069 bbb929c8-8fbe-4397-9dbb-9b2b20218538