Add a couple asserts to baselinePosition implementations.

Hopefully, this will make expected semantics a bit clearer
to newcomers to this code.

R=leviw@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/14575002

git-svn-id: svn://svn.chromium.org/blink/trunk@149409 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Convert cross-fade-list-style-image to ref-test

BUG=235752

Review URL: https://chromiumcodereview.appspot.com/14143006

git-svn-id: svn://svn.chromium.org/blink/trunk@149410 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Convert play-state-paused to ref-test

BUG=235752

Review URL: https://chromiumcodereview.appspot.com/14517002

git-svn-id: svn://svn.chromium.org/blink/trunk@149411 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove libxml2 2.7.3 hacks

Hacks were added in WebKit r113542 to work around Lion shipping with a super old 
(2009 era) libxml2 that has entity parsing bugs. Chromium compiles with a bundled
verison of libxml2 that's version 2.7.7 instead so we don't have this problem and
can remove this hack.

Review URL: https://chromiumcodereview.appspot.com/14603003

git-svn-id: svn://svn.chromium.org/blink/trunk@149412 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Restore WebSocket layout tests deleted at r148891

Some layout tests were deleted due to pywebsocket change at r148891.
This CL restore them.

BUG=234541
R=tyoshino
TEST=http/tests/websocket

Review URL: https://chromiumcodereview.appspot.com/13890011

git-svn-id: svn://svn.chromium.org/blink/trunk@149413 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Refactoring InspectorInstrumentation.cpp to simplify code generation

Pushed most of non-boilerplate checks and parameter conversions from InspectorInstrumentation.cpp to relevant agents code.

Unified signatures of agents methods to match those of instrumentation functions (this required some renaming, moving parameters around and sometimes adding unused parameters).

BUG=232160

Review URL: https://chromiumcodereview.appspot.com/14031038

git-svn-id: svn://svn.chromium.org/blink/trunk@149414 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Rebaseline after fixing anti-aliasing for axis-aligned rectangles.

TBR=jamesr
BUG=169374

Review URL: https://codereview.chromium.org/14621002

git-svn-id: svn://svn.chromium.org/blink/trunk@149415 bbb929c8-8fbe-4397-9dbb-9b2b20218538