Refactors RenderWidget to extract a PaintAggregator class.

After this change, I plan on changing the PaintAggregator algorithm.

Some things to note:

1- Previously, it was possible to send overlapping ViewHostMsg_PaintRect and
ViewHostMsg_ScrollRect messages.  This happened when scrolling a page since the
scrollbar would need to be repainted while the contents of the page are being
scrolled.  With this CL, this overlapping behavior is a bit more explicit.

2- There was a TODO about view_size clipping that I've eliminated.  I was able
to eliminate it because I realized that it is correct to clip the rects passed
by didInvalidateRect and didScrollRect to the size of the RenderWidget.
Apparently WebKit can sometimes invalidate regions outside the view.

R=brettw
BUG=25905
TEST=none

Review URL: http://codereview.chromium.org/403005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@32496 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 4 insertions, 14 deletions

diff --git a/chrome/renderer/render_widget.h b/chrome/renderer/render_widget.h
index df17bd1..31eee61 100644
--- a/chrome/renderer/render_widget.h
+++ b/chrome/renderer/render_widget.h
@@ -14,6 +14,7 @@
 #include "base/gfx/size.h"
 #include "base/ref_counted.h"
 #include "base/shared_memory.h"
+#include "chrome/renderer/paint_aggregator.h"
 #include "chrome/renderer/render_process.h"
 #include "ipc/ipc_channel.h"
 #include "skia/ext/platform_canvas.h"
@@ -120,10 +121,8 @@ class RenderWidget : public IPC::Channel::Listener,
   // must ensure that the given rect fits within the bounds of the WebWidget.
   void PaintRect(const gfx::Rect& rect, skia::PlatformCanvas* canvas);
 
-  void CallDoDeferredPaint();
-  void DoDeferredPaint();
-  void CallDoDeferredScroll();
-  void DoDeferredScroll();
+  void CallDoDeferredUpdate();
+  void DoDeferredUpdate();
   void DoDeferredClose();
   void DoDeferredSetWindowRect(const WebKit::WebRect& pos);
 
@@ -240,20 +239,11 @@ class RenderWidget : public IPC::Channel::Listener,
   TransportDIB* current_paint_buf_;
   TransportDIB* current_scroll_buf_;
 
-  // The smallest bounding rectangle that needs to be re-painted.  This is non-
-  // empty if a paint event is pending.
-  gfx::Rect paint_rect_;
-
-  // The clip rect for the pending scroll event.  This is non-empty if a
-  // scroll event is pending.
-  gfx::Rect scroll_rect_;
+  PaintAggregator paint_aggregator_;
 
   // The area that must be reserved for drawing the resize corner.
   gfx::Rect resizer_rect_;
 
-  // The scroll delta for a pending scroll event.
-  gfx::Point scroll_delta_;
-
   // Flags for the next ViewHostMsg_PaintRect message.
   int next_paint_flags_;