2 files changed, 16 insertions, 30 deletions

diff --git a/webkit/tools/test_shell/gtk/webwidget_host.cc b/webkit/tools/test_shell/gtk/webwidget_host.cc
index 029b27c..5700fca 100644
--- a/webkit/tools/test_shell/gtk/webwidget_host.cc
+++ b/webkit/tools/test_shell/gtk/webwidget_host.cc
@@ -28,6 +28,8 @@ gboolean ConfigureEvent(GtkWidget* widget, GdkEventConfigure* config,
 
 gboolean ExposeEvent(GtkWidget* widget, GdkEventExpose* expose,
                      WebWidgetHost* host) {
+  gfx::Rect rect(expose->area);
+  host->UpdatePaintRect(rect);
   host->Paint();
   return FALSE;
 }
@@ -135,39 +137,23 @@ WebWidgetHost* WebWidgetHost::Create(gfx::WindowHandle box,
   return host;
 }
 
+void WebWidgetHost::UpdatePaintRect(const gfx::Rect& rect) {
+  paint_rect_ = paint_rect_.Union(rect);
+}
+
 void WebWidgetHost::DidInvalidateRect(const gfx::Rect& damaged_rect) {
   DLOG_IF(WARNING, painting_) << "unexpected invalidation while painting";
 
-  // If this invalidate overlaps with a pending scroll, then we have to
-  // downgrade to invalidating the scroll rect.
-  if (damaged_rect.Intersects(scroll_rect_)) {
-    paint_rect_ = paint_rect_.Union(scroll_rect_);
-    ResetScrollRect();
-  }
-  paint_rect_ = paint_rect_.Union(damaged_rect);
+  UpdatePaintRect(damaged_rect);
 
   gtk_widget_queue_draw_area(GTK_WIDGET(view_), damaged_rect.x(),
       damaged_rect.y(), damaged_rect.width(), damaged_rect.height());
 }
 
 void WebWidgetHost::DidScrollRect(int dx, int dy, const gfx::Rect& clip_rect) {
-  DCHECK(dx || dy);
-
-  // If we already have a pending scroll operation or if this scroll operation
-  // intersects the existing paint region, then just failover to invalidating.
-  if (!scroll_rect_.IsEmpty() || paint_rect_.Intersects(clip_rect)) {
-    paint_rect_ = paint_rect_.Union(scroll_rect_);
-    ResetScrollRect();
-    paint_rect_ = paint_rect_.Union(clip_rect);
-  }
-
-  // We will perform scrolling lazily, when requested to actually paint.
-  scroll_rect_ = clip_rect;
-  scroll_dx_ = dx;
-  scroll_dy_ = dy;
-
-  gtk_widget_queue_draw_area(GTK_WIDGET(view_), clip_rect.x(), clip_rect.y(),
-                             clip_rect.width(), clip_rect.height());
+  // This is used for optimizing painting when the renderer is scrolled. We're
+  // currently not doing any optimizations so just invalidate the region.
+  DidInvalidateRect(clip_rect);
 }
 
 WebWidgetHost* FromWindow(gfx::WindowHandle view) {
@@ -217,9 +203,6 @@ void WebWidgetHost::Paint() {
   // This may result in more invalidation
   webwidget_->Layout();
 
-  // TODO(agl): Optimized scrolling code would go here.
-  ResetScrollRect();
-
   // Paint the canvas if necessary.  Allow painting to generate extra rects the
   // first time we call it.  This is necessary because some WebCore rendering
   // objects update their layout only when painted.
@@ -247,9 +230,8 @@ void WebWidgetHost::Paint() {
 }
 
 void WebWidgetHost::ResetScrollRect() {
-  scroll_rect_ = gfx::Rect();
-  scroll_dx_ = 0;
-  scroll_dy_ = 0;
+  // This method is only needed for optimized scroll painting, which we don't
+  // care about in the test shell, yet.
 }
 
 void WebWidgetHost::PaintRect(const gfx::Rect& rect) {
diff --git a/webkit/tools/test_shell/webwidget_host.h b/webkit/tools/test_shell/webwidget_host.h
index 583c9bf..3bc2ac8 100644
--- a/webkit/tools/test_shell/webwidget_host.h
+++ b/webkit/tools/test_shell/webwidget_host.h
@@ -83,6 +83,10 @@ class WebWidgetHost {
   static gfx::WindowHandle CreateWindow(gfx::WindowHandle parent, void* host);
   void WindowDestroyed();
   void Resize(const gfx::Size& size);
+  
+  // Allow clients to update the paint rect. For example, if we get a gdk
+  // expose event, we need to update the paint rect.
+  void UpdatePaintRect(const gfx::Rect& rect);
 #endif
 
   void TrackMouseLeave(bool enable);