A thread-safe Media Query Parser

Implement a thread-safe Media Query parser based on eseidel's tokenizer (https://codereview.chromium.org/123053002/).

This CL is composed of 2 parts:
* Rendering the MediaQuery related classes thread-safe, by eliminating AtomicStrings and replacing them with hash comparisons.
* Replacing BisonCSSParser for a new parser for MQ parsing.

BUG=

Review URL: https://codereview.chromium.org/171383002

git-svn-id: svn://svn.chromium.org/blink/trunk@169289 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Update TestExpectations: gardening.

virtual/threaded/animations/transition-and-animation-2.html flaky on mac also.

BUG=248938
TEST=
TBR=zmo@chromium.org

Review URL: https://codereview.chromium.org/195893024

git-svn-id: svn://svn.chromium.org/blink/trunk@169290 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Layout Test svg/batik/text/textPosition2.svg is flaky

BUG=352856
TEST=
TBR=zmo@chromium.org

Review URL: https://codereview.chromium.org/196983020

git-svn-id: svn://svn.chromium.org/blink/trunk@169291 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Revert 169289 "A thread-safe Media Query Parser"

A bunch of builders failing compile step.

http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Mac%20Oilpan/builds/2093/steps/compile/logs/stdio

http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20Oilpan/builds/2319/steps/compile/logs/stdio

> A thread-safe Media Query Parser
> 
> Implement a thread-safe Media Query parser based on eseidel's tokenizer (https://codereview.chromium.org/123053002/).
> 
> This CL is composed of 2 parts:
> * Rendering the MediaQuery related classes thread-safe, by eliminating AtomicStrings and replacing them with hash comparisons.
> * Replacing BisonCSSParser for a new parser for MQ parsing.
> 
> BUG=
> 
> Review URL: https://codereview.chromium.org/171383002

TBR=yoav@yoav.ws

Review URL: https://codereview.chromium.org/196653020

git-svn-id: svn://svn.chromium.org/blink/trunk@169292 bbb929c8-8fbe-4397-9dbb-9b2b20218538