Cache contains only ascii in StringImpl

third_party/WebKit/Source/wtf/text/StringImpl.cpp

Index: third_party/WebKit/Source/wtf/text/StringImpl.cpp
diff --git a/third_party/WebKit/Source/wtf/text/StringImpl.cpp b/third_party/WebKit/Source/wtf/text/StringImpl.cpp
index 33fdda4d1f6818aa06f101c44415689bcf2a8b6c..641fbc9c72c4b7aeecf2ff0d48498bb7d27e2e20 100644
--- a/third_party/WebKit/Source/wtf/text/StringImpl.cpp
+++ b/third_party/WebKit/Source/wtf/text/StringImpl.cpp
@@ -305,6 +305,13 @@ void StringImpl::destroyIfNotStatic() {
     delete this;
 }
 
+void StringImpl::updateContainsOnlyASCII() const {
+  m_containsOnlyASCII = is8Bit()
+                            ? charactersAreAllASCII(characters8(), length())
+                            : charactersAreAllASCII(characters16(), length());
+  m_needsASCIICheck = false;
+}
+
 bool StringImpl::isSafeToSendToAnotherThread() const {
   if (isStatic())
     return true;