Split out CSSParser public API

Source/core/core.gypi

Index: Source/core/core.gypi
diff --git a/Source/core/core.gypi b/Source/core/core.gypi
index c9c987e191b183c07477063a85ce2734ee42bab6..3bc2efb923a44a1fac66477b93d914c0b1e1843e 100644
--- a/Source/core/core.gypi
+++ b/Source/core/core.gypi
@@ -615,17 +615,17 @@
             'css/CSSBorderImage.h',
             'css/CSSBorderImageSliceValue.cpp',
             'css/CSSBorderImageSliceValue.h',
-            'css/CSSCanvasValue.cpp',
-            'css/CSSCanvasValue.h',
             'css/CSSCalculationValue.cpp',
             'css/CSSCalculationValue.h',
+            'css/CSSCanvasValue.cpp',
+            'css/CSSCanvasValue.h',
             'css/CSSCharsetRule.cpp',
             'css/CSSCharsetRule.h',
             'css/CSSComputedStyleDeclaration.cpp',
             'css/CSSCrossfadeValue.cpp',
             'css/CSSCrossfadeValue.h',
-            'css/CSSCustomFontData.h',
             'css/CSSCursorImageValue.cpp',
+            'css/CSSCustomFontData.h',
             'css/CSSDefaultStyleSheets.cpp',
             'css/CSSDefaultStyleSheets.h',
             'css/CSSFilterRule.cpp',
@@ -674,10 +674,10 @@
             'css/CSSLengthFunctions.cpp',
             'css/CSSLengthFunctions.h',
             'css/CSSLineBoxContainValue.cpp',
-            'css/CSSMatrix.cpp',
-            'css/CSSMatrix.h',
             'css/CSSMarkup.cpp',
             'css/CSSMarkup.h',
+            'css/CSSMatrix.cpp',
+            'css/CSSMatrix.h',
             'css/CSSMediaRule.cpp',
             'css/CSSMediaRule.h',
             'css/CSSMixFunctionValue.cpp',
@@ -686,7 +686,6 @@
             'css/CSSOMUtils.h',
             'css/CSSPageRule.cpp',
             'css/CSSPageRule.h',
-            'css/parser/BisonCSSParser.h',
             'css/CSSParserMode.cpp',
             'css/CSSParserMode.h',
             'css/CSSParserValues.cpp',
@@ -819,10 +818,13 @@
             'css/StyleSheetContents.h',
             'css/StyleSheetList.cpp',
             'css/StyleSheetList.h',
-            'css/VariablesIterator.cpp',
-            'css/VariablesIterator.h',
             'css/TreeBoundaryCrossingRules.cpp',
             'css/TreeBoundaryCrossingRules.h',
+            'css/VariablesIterator.cpp',
+            'css/VariablesIterator.h',
+            'css/parser/BisonCSSParser.h',
+            'css/parser/CSSParser.cpp',
+            'css/parser/CSSParser.h',
             'css/resolver/AnimatedStyleBuilder.cpp',
             'css/resolver/AnimatedStyleBuilder.h',
             'css/resolver/CSSToStyleMap.cpp',