Replace StringImpl::empty{16Bit}() with a static member

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

Index: third_party/WebKit/Source/wtf/text/WTFString.cpp
diff --git a/third_party/WebKit/Source/wtf/text/WTFString.cpp b/third_party/WebKit/Source/wtf/text/WTFString.cpp
index 22c6d0b4e97461aee4ce87293a11573f2b310e0c..95c41594c0c90ad1e6b16fbc08999f564f5a89b6 100644
--- a/third_party/WebKit/Source/wtf/text/WTFString.cpp
+++ b/third_party/WebKit/Source/wtf/text/WTFString.cpp
@@ -251,7 +251,7 @@ void String::ensure16Bit() {
     m_impl =
         make16BitFrom8BitSource(m_impl->characters8(), length).releaseImpl();
   else
-    m_impl = StringImpl::empty16Bit();
+    m_impl = StringImpl::empty16Bit;
 }
 
 void String::truncate(unsigned length) {
@@ -776,12 +776,12 @@ String String::fromUTF8WithLatin1Fallback(const LChar* string, size_t size) {
 }
 
 const String& emptyString() {
-  DEFINE_STATIC_LOCAL(String, emptyString, (StringImpl::empty()));
+  DEFINE_STATIC_LOCAL(String, emptyString, (StringImpl::empty));
   return emptyString;
 }
 
 const String& emptyString16Bit() {
-  DEFINE_STATIC_LOCAL(String, emptyString, (StringImpl::empty16Bit()));
+  DEFINE_STATIC_LOCAL(String, emptyString, (StringImpl::empty16Bit));
   return emptyString;
 }