Use emptyString() for String fields in SecurityOrigin

third_party/WebKit/Source/platform/weborigin/SecurityOrigin.cpp

Index: third_party/WebKit/Source/platform/weborigin/SecurityOrigin.cpp
diff --git a/third_party/WebKit/Source/platform/weborigin/SecurityOrigin.cpp b/third_party/WebKit/Source/platform/weborigin/SecurityOrigin.cpp
index b94f3b24b5f3bff6702218a0c3ad17bba1d8f91e..0864fb2effcaedb0cfae82fa01314a5861b9de23 100644
--- a/third_party/WebKit/Source/platform/weborigin/SecurityOrigin.cpp
+++ b/third_party/WebKit/Source/platform/weborigin/SecurityOrigin.cpp
@@ -115,8 +115,9 @@ static bool shouldTreatAsUniqueOrigin(const KURL& url) {
 }
 
 SecurityOrigin::SecurityOrigin(const KURL& url)
-    : m_protocol(url.protocol().isNull() ? "" : url.protocol().lower()),
-      m_host(url.host().isNull() ? "" : url.host().lower()),
+    : m_protocol(url.protocol().isNull() ? emptyString()
+                                         : url.protocol().lower()),
+      m_host(url.host().isNull() ? emptyString() : url.host().lower()),
       m_port(url.port()),
       m_effectivePort(url.port() ? url.port()
                                  : defaultPortForProtocol(m_protocol)),
@@ -142,9 +143,9 @@ SecurityOrigin::SecurityOrigin(const KURL& url)
 }
 
 SecurityOrigin::SecurityOrigin()
-    : m_protocol(""),
-      m_host(""),
-      m_domain(""),
+    : m_protocol(emptyString()),
+      m_host(emptyString()),
+      m_domain(emptyString()),
       m_port(InvalidPort),
       m_effectivePort(InvalidPort),
       m_isUnique(true),