Write mojom and StructTraits for DisplaySnapshot.

ui/display/types/display_mode.cc

 // 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.
 
 #include "ui/display/types/display_mode.h"
 
 #include "base/memory/ptr_util.h"
 #include "base/strings/stringprintf.h"
 
 namespace display {
 
 DisplayMode::DisplayMode(const gfx::Size& size,
                          bool interlaced,
                          float refresh_rate)
     : size_(size),
       is_interlaced_(interlaced),
       refresh_rate_(refresh_rate) {}
 
 DisplayMode::~DisplayMode() {}
 
 std::unique_ptr<DisplayMode> DisplayMode::Clone() const {
   return base::WrapUnique(new DisplayMode(size_,
                                           is_interlaced_,
                                           refresh_rate_));
 }
 
+bool DisplayMode::operator==(const DisplayMode& other) const {
+  return this->size() == display_mode.size() &&
+         this->is_interlaced() == display_mode.is_interlaced() &&
+         this->refresh_rate() == display_mode.refresh_rate();
+}
+
+bool DisplayMode::operator!=(const DisplayMode& other) const {
+  return !operator==(other);
+}
+
 std::string DisplayMode::ToString() const {
   return base::StringPrintf("[%dx%d %srate=%f]",
                             size_.width(),
                             size_.height(),
                             is_interlaced_ ? "interlaced " : "",
                             refresh_rate_);
 }
 
 void PrintTo(const DisplayMode& mode, std::ostream* os) {
   *os << mode.ToString();
 }
 
 }  // namespace display