Compare relative url if absolute urls are empty for CSSImageValue

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

Index: third_party/WebKit/Source/core/css/CSSImageValue.cpp
diff --git a/third_party/WebKit/Source/core/css/CSSImageValue.cpp b/third_party/WebKit/Source/core/css/CSSImageValue.cpp
index 2c338c86573c6d5c7405a4e79e87606a403d927f..c119d1b61e9c332d61befb003bfdae5b72116d11 100644
--- a/third_party/WebKit/Source/core/css/CSSImageValue.cpp
+++ b/third_party/WebKit/Source/core/css/CSSImageValue.cpp
@@ -102,6 +102,8 @@ bool CSSImageValue::hasFailedOrCanceledSubresources() const {
 }
 
 bool CSSImageValue::equals(const CSSImageValue& other) const {
+  if (m_absoluteURL.isEmpty() && other.m_absoluteURL.isEmpty())
+    return m_relativeURL == other.m_relativeURL;
   return m_absoluteURL == other.m_absoluteURL;
 }