mojo/common: Decouple GURL dependency

mojo/common/common_type_converters.h

Index: mojo/common/common_type_converters.h
diff --git a/mojo/common/common_type_converters.h b/mojo/common/common_type_converters.h
index 8ba270808686db42c0057d54216483953d48f2af..a45f00b3ca45323ca94d58dff9322097714dd07c 100644
--- a/mojo/common/common_type_converters.h
+++ b/mojo/common/common_type_converters.h
@@ -12,8 +12,6 @@
 #include "third_party/mojo/src/mojo/public/cpp/bindings/string.h"
 #include "third_party/mojo/src/mojo/public/cpp/bindings/type_converter.h"
 
-class GURL;
-
 namespace mojo {
 
 template <>
@@ -36,16 +34,6 @@ struct MOJO_COMMON_EXPORT TypeConverter<base::string16, String> {
   static base::string16 Convert(const String& input);
 };
 
-template <>
-struct MOJO_COMMON_EXPORT TypeConverter<String, GURL> {
-  static String Convert(const GURL& input);
-};
-
-template <>
-struct MOJO_COMMON_EXPORT TypeConverter<GURL, String> {
-  static GURL Convert(const String& input);
-};
-
 // TODO(erg): In the very long term, we will want to remove conversion between
 // std::strings and arrays of unsigned bytes. However, there is too much code
 // across chrome which uses std::string as a bag of bytes that we probably