Call WTFString::split(UChar, Vector&) when possible

Source/core/timing/Performance.cpp

Index: Source/core/timing/Performance.cpp
diff --git a/Source/core/timing/Performance.cpp b/Source/core/timing/Performance.cpp
index 318553900ded868ef0090914be466a87413a63a7..6029829a1130437d17209a9b95938227867f6139 100644
--- a/Source/core/timing/Performance.cpp
+++ b/Source/core/timing/Performance.cpp
@@ -174,7 +174,7 @@ static bool passesTimingAllowCheck(const ResourceResponse& response, Document* r
 
     const String& securityOrigin = requestingDocument->securityOrigin()->toString();
     Vector<String> timingAllowOrigins;
-    timingAllowOriginString.string().split(" ", timingAllowOrigins);
+    timingAllowOriginString.string().split(' ', timingAllowOrigins);
     for (size_t i = 0; i < timingAllowOrigins.size(); ++i) {
         if (timingAllowOrigins[i] == securityOrigin)
             return true;