Credential manager: Convert strings to URLs early.

Source/platform/credentialmanager/PlatformCredential.h

Index: Source/platform/credentialmanager/PlatformCredential.h
diff --git a/Source/platform/credentialmanager/PlatformCredential.h b/Source/platform/credentialmanager/PlatformCredential.h
index 0881bf846a5ec26243d408d02d11142c9b86d557..2377dbf2b9c51ffb579d54b96aef706043cdaf13 100644
--- a/Source/platform/credentialmanager/PlatformCredential.h
+++ b/Source/platform/credentialmanager/PlatformCredential.h
@@ -6,6 +6,7 @@
 #define PlatformCredential_h
 
 #include "platform/heap/Handle.h"
+#include "platform/weborigin/KURL.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
@@ -15,22 +16,22 @@ class WebPlatformCredential;
 class PLATFORM_EXPORT PlatformCredential : public GarbageCollectedFinalized<PlatformCredential> {
     WTF_MAKE_NONCOPYABLE(PlatformCredential);
 public:
-    static PlatformCredential* create(const String& id, const String& name, const String& avatarURL);
+    static PlatformCredential* create(const String& id, const String& name, const KURL& avatarURL);
     virtual ~PlatformCredential();
 
     const String& id() const { return m_id; }
     const String& name() const { return m_name; }
-    const String& avatarURL() const { return m_avatarURL; }
+    const KURL& avatarURL() const { return m_avatarURL; }
 
     virtual void trace(Visitor*) { }
 
 protected:
-    PlatformCredential(const String& id, const String& name, const String& avatarURL);
+    PlatformCredential(const String& id, const String& name, const KURL& avatarURL);
 
 private:
     String m_id;
     String m_name;
-    String m_avatarURL;
+    KURL m_avatarURL;
 };
 
 } // namespace blink