Add UseCounter for SVGURIReference.href.baseVal/animVal.

Source/core/core.gypi

 {
     'includes': [
         'core_generated.gypi',
     ],
     'variables': {
         # Files for which bindings (.cpp and .h files) will be generated
         'core_idl_files': [
             'animation/Animation.idl',
             'animation/AnimationEffect.idl',
             'animation/AnimationNode.idl',
@@ skipping 3194 matching lines @@
             'svg/SVGAnimateTransformElement.h',
             'svg/SVGAnimatedAngle.cpp',
             'svg/SVGAnimatedColor.cpp',
             'svg/SVGAnimatedEnumerationBase.cpp',
             'svg/SVGAnimatedInteger.cpp',
             'svg/SVGAnimatedIntegerOptionalInteger.cpp',
             'svg/SVGAnimatedLength.cpp',
             'svg/SVGAnimatedNumber.cpp',
             'svg/SVGAnimatedNumberOptionalNumber.cpp',
             'svg/SVGAnimatedPath.cpp',
+            'svg/SVGAnimatedString.cpp',
+            'svg/SVGAnimatedString.h',
             'svg/SVGAnimatedTypeAnimator.cpp',
             'svg/SVGAnimatedTypeAnimator.h',
             'svg/SVGAnimationElement.cpp',
             'svg/SVGAnimationElement.h',
             'svg/SVGBoolean.cpp',
             'svg/SVGBoolean.h',
             'svg/SVGCircleElement.cpp',
             'svg/SVGCircleElement.h',
             'svg/SVGClipPathElement.cpp',
             'svg/SVGClipPathElement.h',
@@ skipping 597 matching lines @@
             'paint/LayerClipRecorderTest.cpp',
             'paint/LayoutObjectDrawingRecorderTest.cpp',
             'paint/TextPainterTest.cpp',
             'streams/ReadableStreamReaderTest.cpp',
             'streams/ReadableStreamTest.cpp',
             'testing/PrivateScriptTestTest.cpp',
             'xml/parser/SharedBufferReaderTest.cpp',
         ],
     }
 }