Aura: Toggling window mode in about:flags works on CrOS devices

The problem was that programmatically modifying the command line doesn't change switches visible in about:flags -- they are in a special section.  Reworked the code to:
* Not modify the command line when automatically setting the mode.  We now store the mode in ash::Shell.
* Add an "automatic" option for window mode, equivalent to not specifying anything on the command line.

BUG=109002
TEST=aura_shell_unittests for Shell, manual on device modifying about:flags


Review URL: http://codereview.chromium.org/9093002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@116438 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 66 insertions, 44 deletions

diff --git a/ash/ash_switches.cc b/ash/ash_switches.cc
index 21e204f..8ffd94b 100644
--- a/ash/ash_switches.cc
+++ b/ash/ash_switches.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -34,11 +34,5 @@ const char kAuraWindowModeNormal[] = "normal";
 // Use Aura-style workspace window dragging and sizing.
 const char kAuraWorkspaceManager[] = "aura-workspace-manager";
 
-bool IsAuraWindowModeCompact() {
-  std::string mode = CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
-    switches::kAuraWindowMode);
-  return mode == switches::kAuraWindowModeCompact;
-}
-
 }  // namespace switches
 }  // namespace ash
diff --git a/ash/ash_switches.h b/ash/ash_switches.h
index a1044ae..2480bb6 100644
--- a/ash/ash_switches.h
+++ b/ash/ash_switches.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -20,9 +20,6 @@ ASH_EXPORT extern const char kAuraWindowModeCompact[];
 ASH_EXPORT extern const char kAuraWindowModeNormal[];
 ASH_EXPORT extern const char kAuraWorkspaceManager[];
 
-// Utilities for testing multi-valued switches.
-ASH_EXPORT bool IsAuraWindowModeCompact();
-
 }  // namespace switches
 }  // namespace ash
 
diff --git a/ash/shell.cc b/ash/shell.cc
index 77e1c0c..404f0138 100644
--- a/ash/shell.cc
+++ b/ash/shell.cc
@@ -60,7 +60,8 @@ const int kCompactWindowModeWidthThreshold = 1366;
 // Creates each of the special window containers that holds windows of various
 // types in the shell UI. They are added to |containers| from back to front in
 // the z-index.
-void CreateSpecialContainers(aura::Window::Windows* containers) {
+void CreateSpecialContainers(aura::Window::Windows* containers,
+                             bool is_window_mode_compact) {
   aura::Window* background_container = new aura::Window(NULL);
   background_container->set_id(
       internal::kShellWindowId_DesktopBackgroundContainer);
@@ -68,7 +69,7 @@ void CreateSpecialContainers(aura::Window::Windows* containers) {
 
   aura::Window* default_container = new aura::Window(NULL);
   // Primary windows in compact mode don't allow drag, so don't use the filter.
-  if (!switches::IsAuraWindowModeCompact()) {
+  if (!is_window_mode_compact) {
     default_container->SetEventFilter(
         new ToplevelWindowEventFilter(default_container));
   }
@@ -133,7 +134,8 @@ Shell* Shell::instance_ = NULL;
 Shell::Shell(ShellDelegate* delegate)
     : ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)),
       accelerator_controller_(new AcceleratorController),
-      delegate_(delegate) {
+      delegate_(delegate),
+      window_mode_(NORMAL_MODE) {
   aura::RootWindow::GetInstance()->SetEventFilter(
       new internal::RootWindowEventFilter);
 }
@@ -196,10 +198,7 @@ void Shell::Init() {
   // we create containers or layout managers.
   gfx::Size monitor_size = gfx::Screen::GetPrimaryMonitorSize();
   CommandLine* command_line = CommandLine::ForCurrentProcess();
-  if (DefaultToCompactWindowMode(monitor_size, command_line)) {
-    command_line->AppendSwitchASCII(switches::kAuraWindowMode,
-                                    switches::kAuraWindowModeCompact);
-  }
+  window_mode_ = ComputeWindowMode(monitor_size, command_line);
 
   aura::RootWindow* root_window = aura::RootWindow::GetInstance();
   root_window->SetCursor(aura::kCursorPointer);
@@ -207,7 +206,7 @@ void Shell::Init() {
   activation_controller_.reset(new internal::ActivationController);
 
   aura::Window::Windows containers;
-  CreateSpecialContainers(&containers);
+  CreateSpecialContainers(&containers, IsWindowModeCompact());
   aura::Window::Windows::const_iterator i;
   for (i = containers.begin(); i != containers.end(); ++i) {
     (*i)->Init(ui::Layer::LAYER_HAS_NO_TEXTURE);
@@ -242,24 +241,30 @@ void Shell::Init() {
   power_button_controller_.reset(new PowerButtonController);
 }
 
-bool Shell::DefaultToCompactWindowMode(const gfx::Size& monitor_size,
-                                       CommandLine* command_line) const {
-  // Developers often run the Aura shell in a window on their desktop.
-  // Don't mess with their window mode.
-  if (!aura::RootWindow::use_fullscreen_host_window())
-    return false;
+Shell::WindowMode Shell::ComputeWindowMode(const gfx::Size& monitor_size,
+                                           CommandLine* command_line) const {
+  // If user set the flag, use their desired behavior.
+  if (command_line->HasSwitch(switches::kAuraWindowMode)) {
+    std::string mode =
+        command_line->GetSwitchValueASCII(switches::kAuraWindowMode);
+    if (mode == switches::kAuraWindowModeNormal)
+      return NORMAL_MODE;
+    if (mode == switches::kAuraWindowModeCompact)
+      return COMPACT_MODE;
+  }
 
-  // If user set the flag, don't override their desired behavior.
-  if (command_line->HasSwitch(switches::kAuraWindowMode))
-    return false;
+  // Developers often run the Aura shell in small windows on their desktop.
+  // Prefer normal mode for them.
+  if (!aura::RootWindow::use_fullscreen_host_window())
+    return NORMAL_MODE;
 
-  // If the screen is wide enough, we prefer multiple draggable windows.
+  // If the screen is narrow we prefer a single compact window display.
   // We explicitly don't care about height, since users don't generally stack
   // browser windows vertically.
-  if (monitor_size.width() > kCompactWindowModeWidthThreshold)
-    return false;
+  if (monitor_size.width() <= kCompactWindowModeWidthThreshold)
+    return COMPACT_MODE;
 
-  return true;
+  return NORMAL_MODE;
 }
 
 void Shell::InitLayoutManagers(aura::RootWindow* root_window) {
@@ -278,7 +283,7 @@ void Shell::InitLayoutManagers(aura::RootWindow* root_window) {
 
   // Compact mode has a simplified layout manager and doesn't use the launcher,
   // desktop background, shelf, etc.
-  if (switches::IsAuraWindowModeCompact()) {
+  if (IsWindowModeCompact()) {
     default_container->SetLayoutManager(
         new internal::CompactLayoutManager(status_widget));
     internal::CompactStatusAreaLayoutManager* status_area_layout_manager =
diff --git a/ash/shell.h b/ash/shell.h
index 8fb6ffb..88951e8 100644
--- a/ash/shell.h
+++ b/ash/shell.h
@@ -81,6 +81,9 @@ class ASH_EXPORT Shell {
   // Returns true if the screen is locked.
   bool IsScreenLocked() const;
 
+  // See enum WindowMode for details.
+  bool IsWindowModeCompact() const { return window_mode_ == COMPACT_MODE; }
+
   AcceleratorController* accelerator_controller() {
     return accelerator_controller_.get();
   }
@@ -102,19 +105,27 @@ class ASH_EXPORT Shell {
   }
 
  private:
-  FRIEND_TEST_ALL_PREFIXES(ShellTest, DefaultToCompactWindowMode);
+  FRIEND_TEST_ALL_PREFIXES(ShellTest, ComputeWindowMode);
 
   typedef std::pair<aura::Window*, gfx::Rect> WindowAndBoundsPair;
 
+  // In compact window mode we fill the screen with a single maximized window,
+  // similar to ChromeOS R17 and earlier.  In normal mode we have draggable
+  // windows.
+  enum WindowMode {
+    NORMAL_MODE,
+    COMPACT_MODE
+  };
+
   explicit Shell(ShellDelegate* delegate);
   virtual ~Shell();
 
   void Init();
 
-  // Returns true if the |monitor_size| is narrow and the user has not set
-  // an explicit window mode flag on the |command_line|.
-  bool DefaultToCompactWindowMode(const gfx::Size& monitor_size,
-                                  CommandLine* command_line) const;
+  // Returns the appropriate window mode to use based on the primary monitor's
+  // |monitor_size| and the user's |command_line|.
+  WindowMode ComputeWindowMode(const gfx::Size& monitor_size,
+                               CommandLine* command_line) const;
 
   void InitLayoutManagers(aura::RootWindow* root_window);
 
@@ -148,6 +159,9 @@ class ASH_EXPORT Shell {
   // An event filter that pre-handles global accelerators.
   scoped_ptr<internal::AcceleratorFilter> accelerator_filter_;
 
+  // The |window_mode_| never changes after the shell is initialized.
+  // Switching modes requires a restart.
+  WindowMode window_mode_;
 
   DISALLOW_COPY_AND_ASSIGN(Shell);
 };
diff --git a/ash/shell_unittest.cc b/ash/shell_unittest.cc
index 0871ee8..cab9f9f 100644
--- a/ash/shell_unittest.cc
+++ b/ash/shell_unittest.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -264,7 +264,7 @@ TEST_F(ShellTest, IsScreenLocked) {
   EXPECT_FALSE(Shell::GetInstance()->IsScreenLocked());
 }
 
-TEST_F(ShellTest, DefaultToCompactWindowMode) {
+TEST_F(ShellTest, ComputeWindowMode) {
   // We only change default window mode with full-screen host windows.
   AutoResetUseFullscreenHostWindow use_fullscreen_host_window(true);
 
@@ -272,21 +272,33 @@ TEST_F(ShellTest, DefaultToCompactWindowMode) {
   Shell* shell = Shell::GetInstance();
   gfx::Size monitor_size(1440, 900);
   CommandLine command_line(CommandLine::NO_PROGRAM);
-  EXPECT_FALSE(shell->DefaultToCompactWindowMode(monitor_size, &command_line));
+  EXPECT_EQ(Shell::NORMAL_MODE,
+            shell->ComputeWindowMode(monitor_size, &command_line));
 
   // Alex-sized screens need compact mode.
   monitor_size.SetSize(1280, 800);
-  EXPECT_TRUE(shell->DefaultToCompactWindowMode(monitor_size, &command_line));
+  EXPECT_EQ(Shell::COMPACT_MODE,
+            shell->ComputeWindowMode(monitor_size, &command_line));
 
   // ZGB-sized screens need compact mode.
   monitor_size.SetSize(1366, 768);
-  EXPECT_TRUE(shell->DefaultToCompactWindowMode(monitor_size, &command_line));
+  EXPECT_EQ(Shell::COMPACT_MODE,
+            shell->ComputeWindowMode(monitor_size, &command_line));
 
   // Even for a small screen, the user can force normal mode.
   monitor_size.SetSize(800, 600);
   command_line.AppendSwitchASCII(ash::switches::kAuraWindowMode,
                                  ash::switches::kAuraWindowModeNormal);
-  EXPECT_FALSE(shell->DefaultToCompactWindowMode(monitor_size, &command_line));
+  EXPECT_EQ(Shell::NORMAL_MODE,
+            shell->ComputeWindowMode(monitor_size, &command_line));
+
+  // Even for a large screen, the user can force compact mode.
+  monitor_size.SetSize(1920, 1080);
+  CommandLine command_line2(CommandLine::NO_PROGRAM);
+  command_line2.AppendSwitchASCII(ash::switches::kAuraWindowMode,
+                                 ash::switches::kAuraWindowModeCompact);
+  EXPECT_EQ(Shell::COMPACT_MODE,
+            shell->ComputeWindowMode(monitor_size, &command_line2));
 }
 
 }  // namespace ash