Reworked the plumbing required to pass the client resolution to the desktop resizer.

remoting/host/screen_resolution.cc

+// Copyright (c) 2013 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 "remoting/host/screen_resolution.h"
+
+#include <algorithm>
+#include <limits>
+
+namespace remoting {
+
+ScreenResolution::ScreenResolution()
+    : dimensions_(SkISize::Make(0, 0)),
+      dpi_(SkIPoint::Make(0, 0)) {
+}
+
+ScreenResolution::ScreenResolution(const SkISize& dimensions,
+                                   const SkIPoint& dpi)
+    : dimensions_(dimensions),
+      dpi_(dpi) {
+}
+
+SkISize ScreenResolution::ScaleDimensionsToDpi(const SkIPoint& new_dpi) const {
+  // Scale the screen dimensions to new DPI.

[Jamie, 2013/03/15 22:06:27]

DCHECK dpi_ to make sure you're not going to divide by zero (since the default
ctor initializes to that)?

[alexeypa (please no reviews), 2013/03/15 22:32:12]

It will crash nicely even without a DCHECK(). Why bother? 

+  int64 width = std::min(dimensions_.width() * new_dpi.x() / dpi_.x(),
+                         std::numeric_limits<int32>::max());
+  int64 height = std::min(dimensions_.height() * new_dpi.y() / dpi_.y(),
+                          std::numeric_limits<int32>::max());
+
+  return SkISize::Make(static_cast<int32>(width), static_cast<int32>(height));
+}
+
+bool ScreenResolution::IsNull() const {
+  return dimensions_.isEmpty() || dpi_.x() <= 0 || dpi_.y() <= 0;
+}
+
+bool ScreenResolution::IsValid() const {
+  return !IsNull() || dimensions_.isZero();
+}
+
+}  // namespace remoting