Linux: Autodetect whether the custom frame should be used.

Listing a bunch of strings from WMs' source sucks,
but I can't think of any way to detect tiling WMs that
don't support the EWMH (see the bug and the comment in
this CL), so this seems safer.

Tested with the following:
- wiped out related prefs and started chrome under ion3;
  custom frame not used
- quit and started under metacity; custom frame *was* used
- toggled custom frame pref off and restarted under
  metacity again; custom frame not used
- toggled it back on and restarted under ion3; custom frame
  was used

BUG=15861
TEST=see above

Review URL: http://codereview.chromium.org/160374

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@22193 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 56 insertions, 3 deletions

diff --git a/chrome/browser/browser.cc b/chrome/browser/browser.cc
index a23d2ae..35a57d6 100644
--- a/chrome/browser/browser.cc
+++ b/chrome/browser/browser.cc
@@ -1245,7 +1245,6 @@ void Browser::RegisterUserPrefs(PrefService* prefs) {
   prefs->RegisterBooleanPref(prefs::kDeleteFormData, true);
   prefs->RegisterIntegerPref(prefs::kDeleteTimePeriod, 0);
   prefs->RegisterBooleanPref(prefs::kCheckDefaultBrowser, true);
-  prefs->RegisterBooleanPref(prefs::kUseCustomChromeFrame, false);
   prefs->RegisterBooleanPref(prefs::kShowOmniboxSearchHint, true);
 }
 
diff --git a/chrome/browser/browser_prefs.cc b/chrome/browser/browser_prefs.cc
index 57175d6..74e9b65 100644
--- a/chrome/browser/browser_prefs.cc
+++ b/chrome/browser/browser_prefs.cc
@@ -30,7 +30,7 @@
 #include "chrome/browser/views/frame/browser_view.h"
 #endif
 
-#if defined(TOOLKIT_VIEWS) || defined(OS_LINUX)
+#if defined(OS_WIN) || defined(OS_LINUX)
 #include "chrome/browser/task_manager.h"
 #endif
 
@@ -38,6 +38,10 @@
 #include "chrome/browser/views/keyword_editor_view.h"
 #endif
 
+#if defined(TOOLKIT_GTK)
+#include "chrome/browser/gtk/browser_window_gtk.h"
+#endif
+
 namespace browser {
 
 void RegisterAllPrefs(PrefService* user_prefs, PrefService* local_state) {
@@ -56,7 +60,7 @@ void RegisterAllPrefs(PrefService* user_prefs, PrefService* local_state) {
 #if defined(TOOLKIT_VIEWS)  // TODO(port): whittle this down as we port
   BrowserView::RegisterBrowserViewPrefs(local_state);
 #endif
-#if defined(TOOLKIT_VIEWS) || defined(OS_LINUX)
+#if defined(OS_WIN) || defined(OS_LINUX)
   TaskManager::RegisterPrefs(local_state);
 #endif
 
@@ -74,6 +78,9 @@ void RegisterAllPrefs(PrefService* user_prefs, PrefService* local_state) {
   NewTabUI::RegisterUserPrefs(user_prefs);
   BlockedPopupContainer::RegisterUserPrefs(user_prefs);
   DevToolsManager::RegisterUserPrefs(user_prefs);
+#if defined(TOOLKIT_GTK)
+  BrowserWindowGtk::RegisterUserPrefs(user_prefs);
+#endif
 }
 
 }  // namespace browser
diff --git a/chrome/browser/gtk/browser_window_gtk.cc b/chrome/browser/gtk/browser_window_gtk.cc
index 1ffc57c..aef73ad 100644
--- a/chrome/browser/gtk/browser_window_gtk.cc
+++ b/chrome/browser/gtk/browser_window_gtk.cc
@@ -392,6 +392,7 @@ BrowserWindowGtk::BrowserWindowGtk(Browser* browser)
        is_active_(true) {
   use_custom_frame_.Init(prefs::kUseCustomChromeFrame,
       browser_->profile()->GetPrefs(), this);
+
   window_ = GTK_WINDOW(gtk_window_new(GTK_WINDOW_TOPLEVEL));
   g_object_set_data(G_OBJECT(window_), kBrowserWindowKey, this);
   gtk_widget_add_events(GTK_WIDGET(window_), GDK_BUTTON_PRESS_MASK |
@@ -1190,6 +1191,15 @@ GtkWindow* BrowserWindowGtk::GetBrowserWindowForXID(XID xid) {
   return BrowserWindowGtk::xid_map_.find(xid)->second;
 }
 
+// static
+void BrowserWindowGtk::RegisterUserPrefs(PrefService* prefs) {
+  bool custom_frame_default = false;
+  if (!prefs->HasPrefPath(prefs::kUseCustomChromeFrame))
+    custom_frame_default = GetCustomFramePrefDefault();
+  prefs->RegisterBooleanPref(
+      prefs::kUseCustomChromeFrame, custom_frame_default);
+}
+
 void BrowserWindowGtk::SetGeometryHints() {
   // Allow the user to resize us arbitrarily small.
   GdkGeometry geometry;
@@ -1725,3 +1735,34 @@ bool BrowserWindowGtk::GetWindowEdge(int x, int y, GdkWindowEdge* edge) {
   }
   NOTREACHED();
 }
+
+// static
+bool BrowserWindowGtk::GetCustomFramePrefDefault() {
+  XID wm_window;
+  if (!x11_util::GetIntProperty(x11_util::GetX11RootWindow(),
+                                "_NET_SUPPORTING_WM_CHECK",
+                                reinterpret_cast<int*>(&wm_window))) {
+    return false;
+  }
+
+  std::string wm_name;
+  if (!x11_util::GetStringProperty(wm_window, "_NET_WM_NAME", &wm_name))
+    return false;
+
+  // Ideally, we'd use the custom frame by default and just fall back on using
+  // system decorations for the few (?) tiling window managers where it doesn't
+  // make sense (e.g. awesome, ion3, ratpoison, xmonad, etc.).  The EWMH
+  // _NET_SUPPORTING_WM property makes it easy to look up a name for the current
+  // WM, but at least some of the WMs in the latter group don't set it.
+  // Instead, we default to using system decorations for all WMs and
+  // special-case the ones where the custom frame should be used.  These names
+  // are taken from the WMs' source code.
+  return (wm_name == "Blackbox" ||
+          wm_name == "compiz" ||
+          wm_name == "e16" ||  // Enlightenment DR16
+          wm_name == "Fluxbox" ||
+          wm_name == "KWin" ||
+          wm_name == "Metacity" ||
+          wm_name == "Openbox" ||
+          wm_name == "Xfwm4");
+}
diff --git a/chrome/browser/gtk/browser_window_gtk.h b/chrome/browser/gtk/browser_window_gtk.h
index d2e3f2d..acb1d66 100644
--- a/chrome/browser/gtk/browser_window_gtk.h
+++ b/chrome/browser/gtk/browser_window_gtk.h
@@ -164,6 +164,8 @@ class BrowserWindowGtk : public BrowserWindow,
 
   GtkWindow* window() { return window_; }
 
+  static void RegisterUserPrefs(PrefService* prefs);
+
  protected:
   virtual void DestroyBrowser();
   // Top level window.
@@ -277,6 +279,10 @@ class BrowserWindowGtk : public BrowserWindow,
   // it should and sets |edge|.
   bool GetWindowEdge(int x, int y, GdkWindowEdge* edge);
 
+  // Determine whether we use should default to native decorations or the custom
+  // frame based on the currently-running window manager.
+  static bool GetCustomFramePrefDefault();
+
   NotificationRegistrar registrar_;
 
   // The position and size of the current window.