MediaStream API: Patch #1 of implementing navigator.getMediaDevices
The deprecated MediaStreamTrack.getSources()  will be removed later.
This patch contains almost everything except .idl files which means that this is "dead" code which will not affect anything.
Patch 2 will introduce mock support for getMediaDevices.
And finally the third patch will add tests and idl files.

BUG=338511

Review URL: https://codereview.chromium.org/135363004

git-svn-id: svn://svn.chromium.org/blink/trunk@166370 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Correctly accumulate sub-pixel offset into transform origin

In r164561 I added code to properly store and accumulate sub-pixel
offsets into composited layers to avoid pixel-snapping differences
between composited and non-composited content. I missed
accumulating this offset into the code to determine the center of
a composited renderer for use in transforms.

BUG=338674

Review URL: https://codereview.chromium.org/152453002

git-svn-id: svn://svn.chromium.org/blink/trunk@166371 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Add "network-shared-worker.html [ Pass Failure ]" to TestExpectations.

We are moving the worker script loading code to the shared worker process.
http://crbug.com/329786
After this cl (https://codereview.chromium.org/133093003/), the loading task is executed in the worker process.
So "http/tests/inspector/network/network-shared-worker.html" will fail.

See https://groups.google.com/a/chromium.org/forum/#!topic/blink-dev/p1FMy9f8DL8 for more details.

BUG=329786

Review URL: https://codereview.chromium.org/151183002

git-svn-id: svn://svn.chromium.org/blink/trunk@166372 bbb929c8-8fbe-4397-9dbb-9b2b20218538
IDL: allow optional values to be undefined in overload resolution

Recent changes to overload resolution resulted in
　　IDBObjectStore.createIndex
failing (throwing an exception) if the last (optional) argument,
'options', was undefined; concretely:
　　objectStore.createIndex('i', 'p', undefined)

Per Web IDL spec, this should work: the last argument
is optional, and should be treated as missing.

This worked in M33, but failed in M34, though there was
no test case, hence not caught earlier.

This is a conservative fix, patching it so that this case works: 
overloads with an optional non-wrapper type
(primarily Dictionary)
generate an overload resolution check that allows undefined.
This is presumably a rare case; I haven't changed behavior
for optional arguments otherwise.

The full issue is:
Issue 335871: Treat undefined as missing optional arguments
...which is pending Python rewrite and resolution rewrite.

Caused by this CL (r165620):
Add overload support for non-wrapper type vs. primitive type
https://codereview.chromium.org/131973012
...because it made us stricter about undefined
(not allowing undefined on resolution).

BUG=340458

Review URL: https://codereview.chromium.org/152413005

git-svn-id: svn://svn.chromium.org/blink/trunk@166373 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Auto-rebaseline for r166358

http://src.chromium.org/viewvc/blink?view=revision&revision=166358

BUG=337080
TBR=yuki.sekiguchi@access-company.com

Review URL: https://codereview.chromium.org/141553013

git-svn-id: svn://svn.chromium.org/blink/trunk@166374 bbb929c8-8fbe-4397-9dbb-9b2b20218538