Linux: avoid browser windows moving around by the size of WM decorations over restart.

chrome/browser/gtk/browser_window_gtk.cc

Index: chrome/browser/gtk/browser_window_gtk.cc
===================================================================
--- chrome/browser/gtk/browser_window_gtk.cc	(revision 26487)
+++ chrome/browser/gtk/browser_window_gtk.cc	(working copy)
@@ -125,6 +125,16 @@
 // is off.
 const int kCustomFrameBackgroundVerticalOffset = 15;
 
+// When a window is moved or resized, GTK will call MainWindowConfigured below.

[tony, 2009/09/18 18:45:12]

Nit: I expect this comment to either be in the header or near the where we start
the timer.

[Mike Mammarella, 2009/09/18 21:18:40]

Done.

+// The GdkEventConfigure* that we get doesn't have quite the right coordinates
+// though (they're relative to the drawable window area, rather than any window
+// manager decorations, if enabled), so we need to call gtk_window_get_position
+// to get the right values.  (Otherwise session restore, if enabled, will
+// restore windows to incorrect positions.)  That's a round trip to the X server
+// though, so we set a debounce timer and only call it after we haven't seen a
+// reconfigure event in a short while.
+const int kDebounceTimeoutMilliseconds = 100;
+
 base::LazyInstance<ActiveWindowWatcher>
     g_active_window_watcher(base::LINKER_INITIALIZED);
 
@@ -1361,6 +1371,20 @@
   bounds_ = bounds;
   if (!IsFullscreen() && !IsMaximized())
     restored_bounds_ = bounds;
+
+  // We don't use Reset() because the timer may not yet be running.
+  // (In that case Stop() is a no-op.)
+  mainwin_configure_debounce_timer_.Stop();
+  mainwin_configure_debounce_timer_.Start(base::TimeDelta::FromMilliseconds(
+      kDebounceTimeoutMilliseconds), this,
+      &BrowserWindowGtk::OnDebouncedBoundsChanged);
+}
+
+void BrowserWindowGtk::OnDebouncedBoundsChanged() {
+  gint x, y;
+  gtk_window_get_position(window_, &x, &y);
+  gfx::Point origin(x, y);
+  bounds_.set_origin(origin);

[tony, 2009/09/18 18:45:12]

Should we update restored_bounds_ too?

[Mike Mammarella, 2009/09/18 21:18:40]

Done.

   SaveWindowPosition();
 }
 
@@ -1484,13 +1508,16 @@
   maximize_after_show_ = browser_->GetSavedMaximizedState();
 
   gfx::Rect bounds = browser_->GetSavedWindowBounds();
-  // We don't blindly call SetBounds here, that sets a forced position
+  // We don't blindly call SetBounds here: that sets a forced position
   // on the window and we intentionally *don't* do that for normal
-  // windows.  We tested many programs and none of them restored their
-  // position on Linux.
+  // windows.  Most programs do not restore their window position on
+  // Linux, instead letting the window manager choose a position.
   //
   // However, in cases like dropping a tab where the bounds are
-  // specifically set, we do want to position explicitly.
+  // specifically set, we do want to position explicitly.  We also
+  // force the position as part of session restore, as applications
+  // that restore other, similar state (for instance GIMP, audacity,
+  // pidgin, dia, and gkrellm) do tend to restore their positions.
   if (browser_->bounds_overridden()) {
     // For popups, bounds are set in terms of the client area rather than the
     // entire window.