Change TypeConverter<X,Y>::ConvertFrom and ConvertTo into a single symmetric

mojo/public/cpp/bindings/struct_ptr.h

 // Copyright 2014 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.
 
 #ifndef MOJO_PUBLIC_CPP_BINDINGS_STRUCT_PTR_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_STRUCT_PTR_H_
 
 #include <new>
 
 #include "mojo/public/cpp/environment/logging.h"
@@ skipping 23 matching lines @@
   }
 
   StructPtr(RValue other) : ptr_(NULL) { Take(other.object); }
   StructPtr& operator=(RValue other) {
     Take(other.object);
     return *this;
   }
 
   template <typename U>
   U To() const {
-    return TypeConverter<StructPtr, U>::ConvertTo(*this);
+    return TypeConverter<U, StructPtr>::Convert(*this);
   }
 
   void reset() {
     if (ptr_) {
       delete ptr_;
       ptr_ = NULL;
     }
   }
 
   bool is_null() const { return ptr_ == NULL; }
@@ skipping 44 matching lines @@
   ~InlinedStructPtr() {}
 
   InlinedStructPtr(RValue other) : is_null_(true) { Take(other.object); }
   InlinedStructPtr& operator=(RValue other) {
     Take(other.object);
     return *this;
   }
 
   template <typename U>
   U To() const {
-    return TypeConverter<InlinedStructPtr, U>::ConvertTo(*this);
+    return TypeConverter<U, InlinedStructPtr>::Convert(*this);
   }
 
   void reset() {
     is_null_ = true;
     value_.~Struct();
     new (&value_) Struct();
   }
 
   bool is_null() const { return is_null_; }
 
@@ skipping 27 matching lines @@
     Swap(other);
   }
 
   mutable Struct value_;
   bool is_null_;
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_STRUCT_PTR_H_