WIP: Reduce code size of InterfacePtrState

mojo/public/cpp/bindings/interface_ptr_info.h

 // Copyright 2015 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_INTERFACE_PTR_INFO_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_INTERFACE_PTR_INFO_H_
 
 #include <stdint.h>
 #include <utility>
 
 #include "base/macros.h"
 #include "mojo/public/cpp/system/message_pipe.h"
 
 namespace mojo {
 
 // InterfacePtrInfo stores necessary information to communicate with a remote
 // interface implementation, which could be used to construct an InterfacePtr.
-template <typename Interface>
-class InterfacePtrInfo {
+class InterfacePtrInfoBase {
  public:
-  InterfacePtrInfo() : version_(0u) {}
+  InterfacePtrInfoBase();
 
-  InterfacePtrInfo(ScopedMessagePipeHandle handle, uint32_t version)
-      : handle_(std::move(handle)), version_(version) {}
+  InterfacePtrInfoBase(ScopedMessagePipeHandle handle, uint32_t version);
 
-  InterfacePtrInfo(InterfacePtrInfo&& other)
-      : handle_(std::move(other.handle_)), version_(other.version_) {
-    other.version_ = 0u;
-  }
+  InterfacePtrInfoBase(InterfacePtrInfoBase&& other);
 
-  ~InterfacePtrInfo() {}
+  ~InterfacePtrInfoBase();
 
-  InterfacePtrInfo& operator=(InterfacePtrInfo&& other) {
-    if (this != &other) {
-      handle_ = std::move(other.handle_);
-      version_ = other.version_;
-      other.version_ = 0u;
-    }
-
-    return *this;
-  }
+  InterfacePtrInfoBase& operator=(InterfacePtrInfoBase&& other);
 
   bool is_valid() const { return handle_.is_valid(); }
 
   ScopedMessagePipeHandle PassHandle() { return std::move(handle_); }
   const ScopedMessagePipeHandle& handle() const { return handle_; }
   void set_handle(ScopedMessagePipeHandle handle) {
     handle_ = std::move(handle);
   }
 
   uint32_t version() const { return version_; }
   void set_version(uint32_t version) { version_ = version; }
 
  private:
   ScopedMessagePipeHandle handle_;
   uint32_t version_;
 
-  DISALLOW_COPY_AND_ASSIGN(InterfacePtrInfo);
+  DISALLOW_COPY_AND_ASSIGN(InterfacePtrInfoBase);
+};
+
+template <typename Interface>
+class InterfacePtrInfo : public InterfacePtrInfoBase {
+  using InterfacePtrInfoBase::InterfacePtrInfoBase;
 };
 
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_INTERFACE_PTR_INFO_H_