Web Inspector: Track CSS error location information.
https://bugs.webkit.org/show_bug.cgi?id=111314

Source/WebCore:

Added CSS syntax error reporting to some (other rules will be covered later) error recovery grammar rules.
Added code to CSSParser to allow track error location information.
Added empty rule to declaration_list. Needed to not report error about declarations like "body {}".
Added helper grammar rule "errors: error | errors error". Handles the same grammar as "error" but simplifies error location tracking.

Patch by Sergey Ryazanov <serya@chromium.org> on 2013-03-21
Reviewed by Pavel Feldman.

Test: inspector/console/console-css-warnings.html

* css/CSSGrammar.y.in:
* css/CSSParser.cpp:
(WebCore::CSSParser::CSSParser):
(WebCore::CSSParser::currentLocation):
(WebCore):
(WebCore::CSSParser::realLex):
* css/CSSParser.h:
(CSSParser):

LayoutTests:

Patch by Sergey Ryazanov <serya@chromium.org> on 2013-03-21
Reviewed by Pavel Feldman.

* inspector/console/console-css-warnings-expected.txt: Added.
* inspector/console/console-css-warnings.html: Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@146452 268f45cc-cd09-0410-ab3c-d52691b4dbfc