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

ui/gfx/screen_aura.cc

 // Copyright (c) 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 "ui/gfx/screen.h"
 
 #include "base/logging.h"
 #include "ui/gfx/display.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/screen_impl.h"
+#include "ui/gfx/screen_type_delegate.h"
 
 namespace gfx {
 
+#if defined(USE_AURA)
+
 // gfx can't depend upon aura, otherwise we have circular dependencies. So,
 // gfx::Screen is pluggable and Desktop plugs in the real implementation.
-namespace {
-ScreenImpl* g_instance_ = NULL;
+ScreenImpl* g_instance_[SCREEN_TYPE_COUNT];
+ScreenTypeDelegate* g_type_delegate_;
+ScreenType g_screen_type_force_ = SCREEN_TYPE_COUNT;
+
+// TODO(scottmg): This needs to be always given a context object, rather than
+// using global state. It is currently passed BadTwoWorldsContext() == NULL
+// in many places. http://crbug.com/133312
+ScreenImpl* GetImplForContext(NativeView context) {
+  if (!g_type_delegate_)
+    return g_instance_[SCREEN_TYPE_NATIVE];
+  if (g_screen_type_force_ != SCREEN_TYPE_COUNT)
+    return g_instance_[g_screen_type_force_];
+  ScreenType type = g_type_delegate_->GetScreenTypeForNativeView(context);
+  ScreenImpl* screen_impl = g_instance_[type];
+  DCHECK(screen_impl);
+  return screen_impl;
 }
 
 // static
-void Screen::SetInstance(ScreenImpl* screen) {
-  delete g_instance_;
-  g_instance_ = screen;
+void Screen::ForceScreenTypeOverride(ScreenType type) {
+  g_screen_type_force_ = type;
 }
 
 // static
+void Screen::SetInstance(ScreenType type, ScreenImpl* screen) {
+  DCHECK(!g_instance_[type]);
+  g_instance_[type] = screen;
+}
+
+// static
+void Screen::SetScreenTypeDelegate(ScreenTypeDelegate* delegate) {
+  DCHECK(!g_type_delegate_);
+  g_type_delegate_ = delegate;
+}
+
+#endif
+
+// static
 bool Screen::IsDIPEnabled() {
   return true;
 }
 
 // static
-Point Screen::GetCursorScreenPoint() {
-  return g_instance_->GetCursorScreenPoint();
+Point Screen::GetCursorScreenPoint(NativeView context) {
+  return GetImplForContext(context)->GetCursorScreenPoint();
 }
 
 // static
-NativeWindow Screen::GetWindowAtCursorScreenPoint() {
-  return g_instance_->GetWindowAtCursorScreenPoint();
+NativeWindow Screen::GetWindowAtCursorScreenPoint(NativeView context) {
+  return GetImplForContext(context)->GetWindowAtCursorScreenPoint();
 }
 
 // static
-int Screen::GetNumDisplays() {
-  return g_instance_->GetNumDisplays();
+int Screen::GetNumDisplays(NativeView context) {
+  return GetImplForContext(context)->GetNumDisplays();
 }
 
 // static
-Display Screen::GetDisplayNearestWindow(NativeView window) {
-  return g_instance_->GetDisplayNearestWindow(window);
+Display Screen::GetDisplayNearestWindow(NativeView view) {
+  return GetImplForContext(view)->GetDisplayNearestWindow(view);
 }
 
 // static
-Display Screen::GetDisplayNearestPoint(const Point& point) {
-  return g_instance_->GetDisplayNearestPoint(point);
+Display Screen::GetDisplayNearestPoint(NativeView context, const Point& point) {
+  return GetImplForContext(context)->GetDisplayNearestPoint(point);
 }
 
 // static
-Display Screen::GetDisplayMatching(const gfx::Rect& match_rect) {
-  return g_instance_->GetDisplayMatching(match_rect);
+Display Screen::GetDisplayMatching(
+    NativeView context, const gfx::Rect& match_rect) {
+  return GetImplForContext(context)->GetDisplayMatching(match_rect);
 }
 
 // static
-Display Screen::GetPrimaryDisplay() {
-  return g_instance_->GetPrimaryDisplay();
+Display Screen::GetPrimaryDisplay(NativeView context) {
+  return GetImplForContext(context)->GetPrimaryDisplay();
+}
+
+// static
+gfx::NativeView Screen::BadTwoWorldsContext() {
+  // TODO(scottmg): Any calls to this are a bug. http://crbug.com/133312
+  return NULL;
 }
 
 }  // namespace gfx