Add context to gfx::Screen calls in support of simultaneous desktop+ash

chrome/browser/ui/host_desktop.cc

Index: chrome/browser/ui/host_desktop.cc
diff --git a/chrome/browser/ui/host_desktop.cc b/chrome/browser/ui/host_desktop.cc
new file mode 100644
index 0000000000000000000000000000000000000000..ca7b7076fa76a8a8d3c9bd7e18ff0e0a6416b63f
--- /dev/null
+++ b/chrome/browser/ui/host_desktop.cc
@@ -0,0 +1,64 @@
+// Copyright 2012 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 "chrome/browser/ui/host_desktop.h"
+
+#include  "chrome/browser/ui/ash/ash_util.h"
+#include  "chrome/browser/ui/browser_list_impl.h"
+
+namespace chrome {
+
+namespace {
+
+bool force_ = false;
+HostDesktopType force_type_ = HOST_DESKTOP_TYPE_COUNT;
+
+}  // namespace
+
+ScopedForceDesktopType::ScopedForceDesktopType(HostDesktopType type)
+    : previous_type_(force_type_),
+      previous_force_(force_) {
+  force_type_ = type;
+  force_ = true;
+}
+
+ScopedForceDesktopType::~ScopedForceDesktopType() {
+  force_type_ = previous_type_;
+  force_ = previous_force_;
+}
+
+HostDesktopType GetHostDesktopTypeForNativeView(gfx::NativeView native_view) {
+  if (force_)
+    return force_type_;
+  return IsNativeViewInAsh(native_view) ?
+      HOST_DESKTOP_TYPE_ASH :
+      HOST_DESKTOP_TYPE_NATIVE;
+}
+
+HostDesktopType GetHostDesktopTypeForNativeWindow(
+    gfx::NativeWindow native_window) {
+  if (force_)
+    return force_type_;
+  return IsNativeWindowInAsh(native_window) ?
+      HOST_DESKTOP_TYPE_ASH :
+      HOST_DESKTOP_TYPE_NATIVE;
+}
+
+HostDesktopType GetHostDesktopTypeForBrowser(const Browser* browser) {
+  if (force_)
+    return force_type_;
+  for (HostDesktopType type = HOST_DESKTOP_TYPE_FIRST;
+      type < HOST_DESKTOP_TYPE_COUNT;
+      type = static_cast<HostDesktopType>(type + 1)) {
+    BrowserListImpl::const_iterator begin =
+        BrowserListImpl::GetInstance(type)->begin();
+    BrowserListImpl::const_iterator end =
+        BrowserListImpl::GetInstance(type)->end();
+    if (find(begin, end, browser) != end)
+      return type;
+  }
+  return HOST_DESKTOP_TYPE_NATIVE;
+}
+
+}