2 files changed, 13 insertions, 9 deletions
diff --git a/webkit/tools/test_shell/webwidget_host.cc b/webkit/tools/test_shell/webwidget_host.cc
index ca0289e..5c384a5 100644
--- a/webkit/tools/test_shell/webwidget_host.cc
+++ b/webkit/tools/test_shell/webwidget_host.cc
@@ -59,9 +59,14 @@ LRESULT CALLBACK WebWidgetHost::WndProc(HWND hwnd, UINT message, WPARAM wparam,
         delete host;
         break;
 
-      case WM_PAINT:
+      case WM_PAINT: {
+        RECT rect;
+        if (GetUpdateRect(hwnd, &rect, FALSE)) {
+          host->UpdatePaintRect(gfx::Rect(rect));
+        }
         host->Paint();
         return 0;
+      }
 
       case WM_ERASEBKGND:
         // Do nothing here to avoid flashing, the background will be erased
@@ -195,6 +200,10 @@ bool WebWidgetHost::WndProc(UINT message, WPARAM wparam, LPARAM lparam) {
   return false;
 }
 
+void WebWidgetHost::UpdatePaintRect(const gfx::Rect& rect) {
+  paint_rect_ = paint_rect_.Union(rect);
+}
+
 void WebWidgetHost::Paint() {
   RECT r;
   GetClientRect(view_, &r);
diff --git a/webkit/tools/test_shell/webwidget_host.h b/webkit/tools/test_shell/webwidget_host.h
index 4f78744..3bb7b5c 100644
--- a/webkit/tools/test_shell/webwidget_host.h
+++ b/webkit/tools/test_shell/webwidget_host.h
@@ -42,20 +42,15 @@ class WebWidgetHost {
 #endif
 
   void DiscardBackingStore();
+  // Allow clients to update the paint rect. For example, if we get a gdk
+  // expose or WM_PAINT event, we need to update the paint rect.
+  void UpdatePaintRect(const gfx::Rect& rect);
   void Paint();
 
  protected:
   WebWidgetHost();
   ~WebWidgetHost();
 
-#if defined(OS_MACOSX) || defined(OS_LINUX)
- public:
-  // 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);
- protected:
-#endif
-
 #if defined(OS_WIN)
   // Per-class wndproc.  Returns true if the event should be swallowed.
   virtual bool WndProc(UINT message, WPARAM wparam, LPARAM lparam);