Windows: Top-level bubbles no longer appear on taskbar by default.

On Windows, Widget::InitParams::force_show_in_taskbar is now respected,
so it is possible to override the default without having to directly set
HWND properties.

This should not change any behaviour (just a refactor).

Previously, we had a special case where the message center would turn
off showing in taskbar, and app launcher would turn it off for <= Vista.
Now we have just one special case: app launcher turns it on for >= Win7.

BUG=332277

Review URL: https://codereview.chromium.org/127133003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243857 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/ui/views/app_list/win/app_list_service_win.cc

@@ -263,15 +263,6 @@ void CreateAppListShortcuts(
 // Customizes the app list |hwnd| for Windows (eg: disable aero peek, set up
 // restart params).
 void SetWindowAttributes(HWND hwnd) {
-  // Vista and lower do not offer pinning to the taskbar, which makes any
-  // presence on the taskbar useless. So, hide the window on the taskbar
-  // for these versions of Windows.
-  if (base::win::GetVersion() <= base::win::VERSION_VISTA) {
-    LONG_PTR ex_styles = GetWindowLongPtr(hwnd, GWL_EXSTYLE);
-    ex_styles |= WS_EX_TOOLWINDOW;
-    SetWindowLongPtr(hwnd, GWL_EXSTYLE, ex_styles);
-  }
-
   if (base::win::GetVersion() > base::win::VERSION_VISTA) {
     // Disable aero peek. Without this, hovering over the taskbar popup puts
     // Windows into a mode for switching between windows in the same

chrome/browser/ui/views/message_center/message_center_widget_delegate.cc

@@ -149,14 +149,6 @@ void MessageCenterWidgetDelegate::InitWidget() {
 #endif
   widget->Init(params);
 
-#if defined(OS_WIN)
-  // Remove the Message Center from taskbar and alt-tab rotation.
-  HWND hwnd = views::HWNDForWidget(widget);
-  LONG_PTR ex_styles = ::GetWindowLongPtr(hwnd, GWL_EXSTYLE);
-  ex_styles |= WS_EX_TOOLWINDOW;
-  ::SetWindowLongPtr(hwnd, GWL_EXSTYLE, ex_styles);
-#endif
-
   widget->AddObserver(this);
   widget->StackAtTop();
   widget->SetAlwaysOnTop(true);

ui/app_list/views/app_list_view.cc

@@ -6,6 +6,7 @@
 
 #include "base/command_line.h"
 #include "base/strings/string_util.h"
+#include "base/win/windows_version.h"
 #include "ui/app_list/app_list_constants.h"
 #include "ui/app_list/app_list_model.h"
 #include "ui/app_list/app_list_view_delegate.h"
@@ -325,7 +326,13 @@ void AppListView::OnBeforeBubbleWidgetInit(
   if (delegate_ && delegate_->ForceNativeDesktop())
     params->native_widget = new views::DesktopNativeWidgetAura(widget);
 #endif
-#if defined(OS_LINUX)
+#if defined(OS_WIN)
+  // Windows 7 and higher offer pinning to the taskbar, but we need presence
+  // on the taskbar for the user to be able to pin us. So, show the window on
+  // the taskbar for these versions of Windows.
+  if (base::win::GetVersion() >= base::win::VERSION_WIN7)
+    params->force_show_in_taskbar = true;
+#elif defined(OS_LINUX)
   // Set up a custom WM_CLASS for the app launcher window. This allows task
   // switchers in X11 environments to distinguish it from main browser windows.
   params->wm_class_name = kAppListWMClass;

ui/views/widget/widget.h

@@ -227,8 +227,6 @@ class VIEWS_EXPORT Widget : public internal::NativeWidgetDelegate,
     gfx::NativeView 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).
-    // Currently only used by X11.
-    // TODO(mgiuca): Respect this flag in Windows (http://crbug.com/332277).
     bool force_show_in_taskbar;
     // Only used by X11, for root level windows. Specifies the res_name and
     // res_class fields, respectively, of the WM_CLASS window property. Controls

ui/views/widget/widget_hwnd_utils.cc

@@ -122,10 +122,13 @@ void CalculateWindowStylesFromInitParams(
     case Widget::InitParams::TYPE_BUBBLE:
       *style |= WS_POPUP;
       *style |= WS_CLIPCHILDREN;
+      if (!params.force_show_in_taskbar)
+        *ex_style |= WS_EX_TOOLWINDOW;
       break;
     case Widget::InitParams::TYPE_POPUP:
       *style |= WS_POPUP;
-      *ex_style |= WS_EX_TOOLWINDOW;
+      if (!params.force_show_in_taskbar)
+        *ex_style |= WS_EX_TOOLWINDOW;
       break;
     case Widget::InitParams::TYPE_MENU:
       *style |= WS_POPUP;