Remove Clang-on-Win fix for definitions of Color's static data members

Clang does treat the in-class initialization as a definition, just like MSVC.
The problem was that Clang failed to emit the definition unless it was referenced,
which broke the components build. This has been fixed in Clang r213304.

The work-around was added in Blink r176469, and this patch effectively removes that.

BUG=82385

Review URL: https://codereview.chromium.org/397323002

git-svn-id: svn://svn.chromium.org/blink/trunk@178401 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Navigation transitions: Added createStyledMarkupForNavigationTransition

This will be used to serialize markup for transition elements, which is then sent to the transition layer.

BUG=370696

Review URL: https://codereview.chromium.org/281383006

git-svn-id: svn://svn.chromium.org/blink/trunk@178403 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Allow assertions to be enabled in Blink Release builds.

The new GYP/GN variable blink_asserts_always_on (mirroring Chromium's
dcheck_always_on) can be set to 1 to enable assertions in Release
builds.

Tests of NDEBUG related to assertions have been changed to test
ENABLE(ASSERT). Printing/debugging-only code is still guarded under
NDEBUG. Debug-only fields and counters remain debug-only.

Once this CL lands, Blink's assertions will be enabled on the GPU
bots, which only test Release builds (with dcheck_always_on).

Tested:
 - WebGL conformance tests, Release build, asserts on
 - Release build, asserts on, inserted ASSERT(FALSE) guarded under
   ENABLE(ASSERT), verified it was triggered
 - Release build, asserts on, inserted ASSERT(FALSE) guarded under
   ENABLE(SECURITY_ASSERT), verified it was triggered
 - WebGL conformance/context tests, Release build, asserts on, with
   https://codereview.chromium.org/251373005, verified assertion
   failure was triggered
 - WebGL conformance/context tests, Debug build, default assertion
   behavior, with https://codereview.chromium.org/251373005, verified
   assertion failure was triggered
 - wtf_unittests, Release build, asserts on

BUG=393838

Review URL: https://codereview.chromium.org/397733004

git-svn-id: svn://svn.chromium.org/blink/trunk@178404 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: get rid of WebInspector.cssModel, use target models instead

Review URL: https://codereview.chromium.org/396993003

git-svn-id: svn://svn.chromium.org/blink/trunk@178405 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Resolve screen.orientation.lock() promise with undefined.

This is following the current state of the specification.

BUG=162827

Review URL: https://codereview.chromium.org/400703003

git-svn-id: svn://svn.chromium.org/blink/trunk@178406 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Set callback interface on WebCDMSession after creation.

In order to allow MediaKeySession to be created only when resolving
the promise, add the ability to set the client callback interface on
WebContentDecryptionModuleSession after the object is created.

BUG=358271
TEST=EME layouts tests pass

Review URL: https://codereview.chromium.org/379343003

git-svn-id: svn://svn.chromium.org/blink/trunk@178407 bbb929c8-8fbe-4397-9dbb-9b2b20218538