cros: Change default display for new windows without parent or context

Make views::Widget::InitParams::context optional. This cuts some
dependencies between //chrome/browser/ui and //ash, which we need to
do for go/mustash.

Change the default display for windows that supply neither parent nor
context to the "root window for new windows" (i.e. the display where
the user last activated a window). The old behavior was to always use
the primary display. The new behavior is consistent with mash.

Fix a couple cases where windows were defaulting to the primary
display when they should have been using the display for new windows
(e.g. task manager when all browsers are closed).

Bug: 826569
Test: covered by tests
Change-Id: I4571c3c7066b4247559d43e7b1192ef8411f8919
Reviewed-on: https://chromium-review.googlesource.com/988732
Commit-Queue: James Cook <jamescook@chromium.org>
Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#547515}

chrome/browser/chromeos/certificate_provider/pin_dialog_manager.cc

@@ -103,10 +103,9 @@ PinDialogManager::RequestPinResponse PinDialogManager::ShowPinDialog(
                                           attempts_left, callback, this);
 
   gfx::NativeWindow parent = GetBrowserParentWindow();
-  gfx::NativeWindow context =
-      parent ? nullptr : ash::Shell::GetPrimaryRootWindow();
-  active_window_ = views::DialogDelegate::CreateDialogWidget(active_pin_dialog_,
-                                                             context, parent);
+  // If there is no parent, falls back to the root window for new windows.
+  active_window_ = views::DialogDelegate::CreateDialogWidget(
+      active_pin_dialog_, /*context=*/ nullptr, parent);
   active_window_->Show();
 
   return SUCCESS;

chrome/browser/chromeos/power/idle_action_warning_dialog_view.cc

@@ -72,8 +72,10 @@ IdleActionWarningDialogView::IdleActionWarningDialogView(
 
   UpdateLabel();
 
-  views::DialogDelegate::CreateDialogWidget(
-      this, ash::Shell::GetPrimaryRootWindow(), NULL)->Show();
+  // Shown on the root window for new windows.
+  views::DialogDelegate::CreateDialogWidget(this, nullptr /* context */,
+                                            nullptr /* parent */)
+      ->Show();
 
   update_timer_.Start(
       FROM_HERE,

chrome/browser/ui/views/chrome_views_delegate_chromeos.cc

@@ -75,18 +75,11 @@ ChromeViewsDelegate::GetOpacityForInitParams(
 views::NativeWidget* ChromeViewsDelegate::CreateNativeWidget(
     views::Widget::InitParams* params,
     views::internal::NativeWidgetDelegate* delegate) {
-  // When we are doing straight chromeos builds, we still need to handle the
-  // toplevel window case.
-  // There may be a few remaining widgets in Chrome OS that are not top level,
-  // but have neither a context nor a parent. Provide a fallback context so
-  // users don't crash. Developers will hit the DCHECK and should provide a
-  // context.
-  if (params->context)
-    params->context = params->context->GetRootWindow();
-  DCHECK(params->parent || params->context || !params->child)
-      << "Please provide a parent or context for this widget.";
-  if (!params->parent && !params->context)
-    params->context = ash::Shell::GetPrimaryRootWindow();
+  // Classic ash requires a parent or a context that it can use to look up a
+  // root window to find a WindowParentingClient. Mash handles window parenting
+  // inside ash, see ash::CreateAndParentTopLevelWindow().
+  if (!ash_util::IsRunningInMash() && !params->parent && !params->context)
+    params->context = ash::Shell::GetRootWindowForNewWindows();
 
   // By returning null Widget creates the default NativeWidget implementation,
   // which for chromeos is NativeWidgetAura.

chrome/browser/ui/views/frame/browser_frame_ash.cc

@@ -8,15 +8,17 @@
 
 // This file is only instantiated in classic ash/mus. It is never used in mash.
 // See native_browser_frame_factory_chromeos.cc switches on GetAshConfig().
-#include "ash/public/cpp/window_properties.h"  // mash-ok
-#include "ash/public/cpp/window_state_type.h"  // mash-ok
-#include "ash/shell.h"                         // mash-ok
-#include "ash/wm/window_properties.h"          // mash-ok
-#include "ash/wm/window_state.h"               // mash-ok
-#include "ash/wm/window_state_delegate.h"      // mash-ok
-#include "ash/wm/window_util.h"                // mash-ok
+#include "ash/public/cpp/config.h"
+#include "ash/public/cpp/window_properties.h"
+#include "ash/public/cpp/window_state_type.h"
+#include "ash/shell.h"                     // mash-ok
+#include "ash/wm/window_properties.h"      // mash-ok
+#include "ash/wm/window_state.h"           // mash-ok
+#include "ash/wm/window_state_delegate.h"  // mash-ok
+#include "ash/wm/window_util.h"            // mash-ok
 #include "base/macros.h"
 #include "build/build_config.h"
+#include "chrome/browser/chromeos/ash_config.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/browser_finder.h"
 #include "chrome/browser/ui/views/frame/browser_view.h"
@@ -61,6 +63,7 @@ BrowserFrameAsh::BrowserFrameAsh(BrowserFrame* browser_frame,
                                  BrowserView* browser_view)
     : views::NativeWidgetAura(browser_frame),
       browser_view_(browser_view) {
+  DCHECK_NE(chromeos::GetAshConfig(), ash::Config::MASH);
   GetNativeWindow()->SetName("BrowserFrameAsh");
   Browser* browser = browser_view->browser();
   ash::wm::WindowState* window_state =

chrome/browser/ui/views/frame/browser_frame_ash.h

@@ -12,7 +12,8 @@
 class BrowserFrame;
 class BrowserView;
 
-// BrowserFrameAsh provides the frame for Chrome browser windows on Chrome OS.
+// BrowserFrameAsh provides the frame for Chrome browser windows on Chrome OS
+// under classic ash.
 class BrowserFrameAsh : public views::NativeWidgetAura,
                         public NativeBrowserFrame {
  public:

chrome/browser/ui/views/frame/browser_frame_mus.cc

@@ -20,11 +20,13 @@
 #include "ui/views/mus/window_manager_frame_values.h"
 
 #if defined(OS_CHROMEOS)
+#include "ash/public/cpp/config.h"
 #include "ash/public/cpp/shelf_types.h"
 #include "ash/public/cpp/window_properties.h"
 #include "ash/public/cpp/window_state_type.h"
 #include "ash/public/interfaces/window_properties.mojom.h"
 #include "ash/public/interfaces/window_style.mojom.h"
+#include "chrome/browser/chromeos/ash_config.h"
 #include "services/ui/public/interfaces/window_manager.mojom.h"
 #endif
 
@@ -32,7 +34,12 @@ BrowserFrameMus::BrowserFrameMus(BrowserFrame* browser_frame,
                                  BrowserView* browser_view)
     : views::DesktopNativeWidgetAura(browser_frame),
       browser_frame_(browser_frame),
-      browser_view_(browser_view) {}
+      browser_view_(browser_view) {
+#if defined(OS_CHROMEOS)
+  // Not used with Mus on Chrome OS.
+  DCHECK_EQ(chromeos::GetAshConfig(), ash::Config::MASH);
+#endif
+}
 
 BrowserFrameMus::~BrowserFrameMus() {}
 

chrome/browser/ui/views/screen_capture_notification_ui_views.cc

@@ -30,7 +30,13 @@
 #endif
 
 #if defined(OS_CHROMEOS)
-#include "ash/shell.h"
+#include "ash/shell.h"  // mash-ok
+#include "chrome/browser/chromeos/ash_config.h"
+#include "mojo/public/cpp/bindings/type_converter.h"
+#include "services/ui/public/cpp/property_type_converters.h"
+#include "services/ui/public/interfaces/window_manager.mojom.h"
+#include "ui/display/display.h"
+#include "ui/display/screen.h"
 #endif
 
 namespace {
@@ -184,8 +190,14 @@ gfx::NativeViewId ScreenCaptureNotificationUIViews::OnStarted(
   // TODO(sergeyu): The notification bar must be shown on the monitor that's
   // being captured. Make sure it's always the case. Currently we always capture
   // the primary monitor.
-  if (ash::Shell::HasInstance())
+  if (chromeos::GetAshConfig() != ash::Config::MASH) {
     params.context = ash::Shell::GetPrimaryRootWindow();
+  } else {
+    const display::Display primary_display =
+        display::Screen::GetScreen()->GetPrimaryDisplay();
+    params.mus_properties[ui::mojom::WindowManager::kDisplayId_InitProperty] =
+        mojo::ConvertTo<std::vector<uint8_t>>(primary_display.id());
+  }
 #endif
 
   widget->set_frame_type(views::Widget::FRAME_TYPE_FORCE_CUSTOM);

chrome/browser/ui/views/task_manager_view.cc

@@ -34,12 +34,9 @@
 #include "ui/views/window/dialog_client_view.h"
 
 #if defined(OS_CHROMEOS)
-// gn check complains on Linux Ozone.
-#include "ash/public/cpp/shelf_item.h"         // nogncheck
-#include "ash/public/cpp/window_properties.h"  // nogncheck
+#include "ash/public/cpp/shelf_item.h"
+#include "ash/public/cpp/window_properties.h"
 #include "ash/resources/grit/ash_resources.h"
-#include "ash/wm/window_util.h"
-#include "chrome/browser/ui/ash/ash_util.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/image/image_skia.h"
@@ -75,13 +72,10 @@ task_manager::TaskManagerTableModel* TaskManagerView::Show(Browser* browser) {
 
   g_task_manager_view = new TaskManagerView();
 
+  // On Chrome OS, pressing Search-Esc when there are no open browser windows
+  // will open the task manager on the root window for new windows.
   gfx::NativeWindow context =
       browser ? browser->window()->GetNativeWindow() : nullptr;
-#if defined(OS_CHROMEOS)
-  if (!ash_util::IsRunningInMash() && !context)
-    context = ash::wm::GetActiveWindow();
-#endif
-
   DialogDelegate::CreateDialogWidget(g_task_manager_view, context, nullptr);
   g_task_manager_view->InitAlwaysOnTopState();
 

ui/views/widget/desktop_aura/desktop_native_widget_aura.h

@@ -51,6 +51,8 @@ class FocusManagerEventHandler;
 class TooltipManagerAura;
 class WindowReorderer;
 
+// DesktopNativeWidgetAura handles top-level widgets on Windows, Linux, and
+// Chrome OS with mash.
 class VIEWS_EXPORT DesktopNativeWidgetAura
     : public internal::NativeWidgetPrivate,
       public aura::WindowDelegate,

ui/views/widget/native_widget_aura.cc

@@ -147,7 +147,6 @@ void NativeWidgetAura::SetShadowElevationFromInitParams(
 // NativeWidgetAura, internal::NativeWidgetPrivate implementation:
 
 void NativeWidgetAura::InitNativeWidget(const Widget::InitParams& params) {
-  // Aura needs to know which desktop (Ash or regular) will manage this widget.
   // See Widget::InitParams::context for details.
   DCHECK(params.parent || params.context);
 

ui/views/widget/widget.h

@@ -276,8 +276,9 @@ class VIEWS_EXPORT Widget : public internal::NativeWidgetDelegate,
     // hierarchy this widget should be placed. (This is separate from |parent|;
     // if you pass a RootWindow to |parent|, your window will be parented to
     // |parent|. If you pass a RootWindow to |context|, we ask that RootWindow
-    // where it wants your window placed.) NULL is not allowed if you are using
-    // aura.
+    // where it wants your window placed.) Nullptr is not allowed on Windows and
+    // Linux. Nullptr is allowed on Chrome OS, which will place the window on
+    // the default desktop for new windows.
     gfx::NativeWindow context;
     // If true, forces the window to be shown in the taskbar, even for window
     // types that do not appear in the taskbar by default (popup and bubble).