Reduce string copies in GURL creation

chrome/renderer/plugins/chrome_plugin_placeholder.cc

Index: chrome/renderer/plugins/chrome_plugin_placeholder.cc
diff --git a/chrome/renderer/plugins/chrome_plugin_placeholder.cc b/chrome/renderer/plugins/chrome_plugin_placeholder.cc
index 6f616672312e7b4b4c255697e67871f727ac3844..ce1b63f13965aea51315842236d61e7157207a63 100644
--- a/chrome/renderer/plugins/chrome_plugin_placeholder.cc
+++ b/chrome/renderer/plugins/chrome_plugin_placeholder.cc
@@ -24,6 +24,7 @@
 #include "content/public/renderer/render_frame.h"
 #include "content/public/renderer/render_thread.h"
 #include "gin/object_template_builder.h"
+#include "third_party/WebKit/public/platform/URLConversion.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
 #include "third_party/WebKit/public/web/WebInputEvent.h"
 #include "third_party/WebKit/public/web/WebLocalFrame.h"
@@ -262,7 +263,7 @@ void ChromePluginPlaceholder::PluginListChanged() {
   render_frame()->Send(
       new ChromeViewHostMsg_GetPluginInfo(routing_id(),
                                           GURL(GetPluginParams().url),
-                                          GURL(top_origin),
+                                          blink::WebStringToGURL(top_origin),
                                           mime_type,
                                           &output));
   if (output.status == status_)