Hide the browser actions gripper when it's not in use.

chrome/browser/gtk/browser_actions_toolbar_gtk.cc

Index: chrome/browser/gtk/browser_actions_toolbar_gtk.cc
diff --git a/chrome/browser/gtk/browser_actions_toolbar_gtk.cc b/chrome/browser/gtk/browser_actions_toolbar_gtk.cc
index b1126bc8e9f81672ef5099466568d3859820abc0..b60489a06ff88649a230e1d1a5ba0bfc660375cc 100644
--- a/chrome/browser/gtk/browser_actions_toolbar_gtk.cc
+++ b/chrome/browser/gtk/browser_actions_toolbar_gtk.cc
@@ -350,6 +350,7 @@ BrowserActionsToolbarGtk::BrowserActionsToolbarGtk(Browser* browser)
       resize_animation_(this),
       desired_width_(0),
       start_width_(0),
+      draw_gripper_(false),
       method_factory_(this) {
   ExtensionsService* extension_service = profile_->GetExtensionsService();
   // The |extension_service| can be NULL in Incognito.
@@ -753,6 +754,9 @@ gboolean BrowserActionsToolbarGtk::OnGripperMotionNotify(
 
 gboolean BrowserActionsToolbarGtk::OnGripperExpose(GtkWidget* gripper,
                                                    GdkEventExpose* expose) {
+  if (!draw_gripper_)
+    return TRUE;
+
   cairo_t* cr = gdk_cairo_create(GDK_DRAWABLE(expose->window));
 
   CairoCachedSurface* surface = theme_provider_->GetSurfaceNamed(
@@ -777,13 +781,18 @@ gboolean BrowserActionsToolbarGtk::OnGripperEnterNotify(
     GtkWidget* gripper, GdkEventCrossing* event) {
   gdk_window_set_cursor(gripper->window,
                         gtk_util::GetCursor(GDK_SB_H_DOUBLE_ARROW));
+  draw_gripper_ = true;

[sky, 2010/07/01 16:40:14]

How come you don't queue_draw here and @ 793?

[Evan Stade, 2010/07/01 17:35:08]

GtkButtons already queue_draw when the mouse enters/leaves (because the hover
state changes, and hence drawing may change). Thus we don't need to call
queue_draw, although it probably wouldn't hurt either.

+
   return FALSE;
 }
 
 gboolean BrowserActionsToolbarGtk::OnGripperLeaveNotify(
     GtkWidget* gripper, GdkEventCrossing* event) {
-  if (!(event->state & GDK_BUTTON1_MASK))
+  if (!(event->state & GDK_BUTTON1_MASK)) {
     gdk_window_set_cursor(gripper->window, NULL);
+    draw_gripper_ = false;
+  }
+
   return FALSE;
 }
 
@@ -792,8 +801,11 @@ gboolean BrowserActionsToolbarGtk::OnGripperButtonRelease(
   gfx::Rect gripper_rect(0, 0,
                          gripper->allocation.width, gripper->allocation.height);
   gfx::Point release_point(event->x, event->y);
-  if (!gripper_rect.Contains(release_point))
+  if (!gripper_rect.Contains(release_point)) {
     gdk_window_set_cursor(gripper->window, NULL);
+    draw_gripper_ = false;
+    gtk_widget_queue_draw(gripper);
+  }
 
   // After the user resizes the toolbar, we want to smartly resize it to be
   // the perfect size to fit the buttons.