PurgeMemory.

third_party/WebKit/Source/core/css/CSSImageSetValue.cpp

Index: third_party/WebKit/Source/core/css/CSSImageSetValue.cpp
diff --git a/third_party/WebKit/Source/core/css/CSSImageSetValue.cpp b/third_party/WebKit/Source/core/css/CSSImageSetValue.cpp
index b68a44a5e156a534db3a60632aa1602f4b0581bb..9ae8f86aab2eaf3ca304f71db7bba1dcc038187d 100644
--- a/third_party/WebKit/Source/core/css/CSSImageSetValue.cpp
+++ b/third_party/WebKit/Source/core/css/CSSImageSetValue.cpp
@@ -185,5 +185,16 @@ PassRefPtrWillBeRawPtr<CSSImageSetValue> CSSImageSetValue::valueWithURLsMadeAbso
     return value.release();
 }
 
+void CSSImageSetValue::purgeMemory()
+{
+    size_t length = this->length();
+    for (size_t i = 0; i < length; i ++) {
+        CSSValue* value = item(i);
+        if (value && value->isImageValue())
+            toCSSImageValue(value)->purgeMemory();
+    }
+    m_imagesInSet.clear();
+    m_cachedImage = nullptr;
+}
 
 } // namespace blink