Reduce string copies in GURL creation

third_party/WebKit/Source/platform/exported/URLConversion.cpp

Index: third_party/WebKit/Source/platform/exported/URLConversion.cpp
diff --git a/third_party/WebKit/Source/platform/exported/URLConversion.cpp b/third_party/WebKit/Source/platform/exported/URLConversion.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..7781613fdafe2d0ef63c4beed47d33a8af859ce1
--- /dev/null
+++ b/third_party/WebKit/Source/platform/exported/URLConversion.cpp
@@ -0,0 +1,30 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "public/platform/URLConversion.h"
+
+#include "public/platform/WebString.h"
+#include "url/gurl.h"
+#include "wtf/text/StringUTF8Adaptor.h"
+#include "wtf/text/WTFString.h"
+
+namespace blink {
+
+GURL WebStringToGURL(const WebString& webString)
+{
+    if (webString.isEmpty())
+        return GURL();
+
+    String str = webString;
+    if (str.is8Bit()) {
+        // Ensure the (possibly Latin-1) 8-bit string is UTF-8 for GURL.
+        StringUTF8Adaptor utf8(str);
+        return GURL(utf8.asStringPiece());
+    }
+
+    // GURL can consume UTF-16 directly.
+    return GURL(base::StringPiece16(str.characters16(), str.length()));
+}
+
+} // namespace blink