[WIP] Add support for CSSValue-> CSSLengthValue and CSSTranslation

third_party/WebKit/Source/core/css/cssom/CSSTranslation.cpp

Index: third_party/WebKit/Source/core/css/cssom/CSSTranslation.cpp
diff --git a/third_party/WebKit/Source/core/css/cssom/CSSTranslation.cpp b/third_party/WebKit/Source/core/css/cssom/CSSTranslation.cpp
index 49e26c1e8ab545c3f0831b19debdc5906e64d833..192b7a1e24977903c68f498fca043bc0f0b65b85 100644
--- a/third_party/WebKit/Source/core/css/cssom/CSSTranslation.cpp
+++ b/third_party/WebKit/Source/core/css/cssom/CSSTranslation.cpp
@@ -18,6 +18,37 @@ CSSTranslation* CSSTranslation::create(CSSLengthValue* x, CSSLengthValue* y, CSS
     return new CSSTranslation(x, y, z);
 }
 
+CSSTranslation* CSSTranslation::fromCSSValue(const CSSValue& value)
+{
+    if (!value.isFunctionValue())
+        return nullptr;
+
+    const CSSFunctionValue& cssFunctionValue = toCSSFunctionValue(value);
+    if (cssFunctionValue.length() < 2)
+        return nullptr;
+
+    CSSLengthValue* x = CSSLengthValue::fromCSSValue(*cssFunctionValue.item(0));
+    CSSLengthValue* y = CSSLengthValue::fromCSSValue(*cssFunctionValue.item(1));
+    if (!x || !y)
+        return nullptr;
+
+    if (cssFunctionValue.functionType() == CSSValueTranslate) {
+        if (cssFunctionValue.length() != 2)
+            return nullptr;
+        return CSSTranslation::create(x, y);
+    }
+
+    if (cssFunctionValue.functionType() == CSSValueTranslate3d) {
+        if (cssFunctionValue.length() != 3)
+            return nullptr;
+        CSSLengthValue* z = CSSLengthValue::fromCSSValue(*cssFunctionValue.item(2));
+        if (!z || z->containsPercent())
+            return nullptr;
+        return new CSSTranslation(x, y, z);
+    }
+    return nullptr;
+}
+
 CSSFunctionValue* CSSTranslation::toCSSValue() const
 {
     CSSFunctionValue* result = CSSFunctionValue::create(is2D() ? CSSValueTranslate : CSSValueTranslate3d);