diff -r 000000000000 -r 4f2f89ce4247 WebKit2/UIProcess/ChunkedUpdateDrawingAreaProxy.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebKit2/UIProcess/ChunkedUpdateDrawingAreaProxy.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,176 @@
+/*
+ * Copyright (C) 2010 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "ChunkedUpdateDrawingAreaProxy.h"
+
+#include "DrawingAreaMessageKinds.h"
+#include "DrawingAreaProxyMessageKinds.h"
+#include "MessageID.h"
+#include "UpdateChunk.h"
+#include "WebCoreArgumentCoders.h"
+#include "WebPageProxy.h"
+#include "WebProcessProxy.h"
+
+using namespace WebCore;
+
+namespace WebKit {
+
+ChunkedUpdateDrawingAreaProxy::ChunkedUpdateDrawingAreaProxy(PlatformWebView* webView)
+    : DrawingAreaProxy(ChunkedUpdateDrawingAreaType)
+    , m_isWaitingForDidSetFrameNotification(false)
+    , m_isVisible(true)
+    , m_forceRepaintWhenResumingPainting(false)
+    , m_webView(webView)
+{
+}
+
+ChunkedUpdateDrawingAreaProxy::~ChunkedUpdateDrawingAreaProxy()
+{
+}
+
+void ChunkedUpdateDrawingAreaProxy::paint(const IntRect& rect, PlatformDrawingContext context)
+{
+    if (m_isWaitingForDidSetFrameNotification) {
+        WebPageProxy* page = this->page();
+        if (!page->isValid())
+            return;
+        
+        if (page->process()->isLaunching())
+            return;
+
+        OwnPtr<CoreIPC::ArgumentDecoder> arguments = page->process()->connection()->waitFor(DrawingAreaProxyMessage::DidSetSize, page->pageID(), 0.04);
+        if (arguments)
+            didReceiveMessage(page->process()->connection(), CoreIPC::MessageID(DrawingAreaProxyMessage::DidSetSize), *arguments.get());
+    }
+
+    platformPaint(rect, context);
+}
+
+void ChunkedUpdateDrawingAreaProxy::setSize(const IntSize& viewSize)
+{
+    WebPageProxy* page = this->page();
+    if (!page->isValid())
+        return;
+
+    if (viewSize.isEmpty())
+        return;
+
+    m_viewSize = viewSize;
+    m_lastSetViewSize = viewSize;
+
+    if (m_isWaitingForDidSetFrameNotification)
+        return;
+    m_isWaitingForDidSetFrameNotification = true;
+
+    page->process()->responsivenessTimer()->start();
+    page->process()->send(DrawingAreaMessage::SetSize, page->pageID(), CoreIPC::In(viewSize));
+}
+
+void ChunkedUpdateDrawingAreaProxy::setPageIsVisible(bool isVisible)
+{
+    WebPageProxy* page = this->page();
+
+    if (isVisible == m_isVisible)
+        return;
+    
+    m_isVisible = isVisible;
+    if (!page->isValid())
+        return;
+
+    if (!m_isVisible) {
+        // Tell the web process that it doesn't need to paint anything for now.
+        page->process()->send(DrawingAreaMessage::SuspendPainting, page->pageID(), CoreIPC::In());
+        return;
+    }
+    
+    // The page is now visible, resume painting.
+    page->process()->send(DrawingAreaMessage::ResumePainting, page->pageID(), CoreIPC::In(m_forceRepaintWhenResumingPainting));
+    m_forceRepaintWhenResumingPainting = false;
+}
+    
+void ChunkedUpdateDrawingAreaProxy::didSetSize(UpdateChunk* updateChunk)
+{
+    ASSERT(m_isWaitingForDidSetFrameNotification);
+    m_isWaitingForDidSetFrameNotification = false;
+
+    IntSize viewSize = updateChunk->rect().size();
+
+    if (viewSize != m_lastSetViewSize)
+        setSize(m_lastSetViewSize);
+
+    invalidateBackingStore();
+    if (!updateChunk->isEmpty())
+        drawUpdateChunkIntoBackingStore(updateChunk);
+
+    WebPageProxy* page = this->page();
+    page->process()->responsivenessTimer()->stop();
+}
+
+void ChunkedUpdateDrawingAreaProxy::update(UpdateChunk* updateChunk)
+{
+    if (!m_isVisible) {
+        // We got an update request that must have been sent before we told the web process to suspend painting.
+        // Don't paint this into the backing store, because that could leave the backing store in an inconsistent state.
+        // Instead, we will just tell the drawing area to repaint everything when we resume painting.
+        m_forceRepaintWhenResumingPainting = true;
+    } else {
+        // Just paint into backing store.
+        drawUpdateChunkIntoBackingStore(updateChunk);
+    }
+
+    WebPageProxy* page = this->page();
+    page->process()->send(DrawingAreaMessage::DidUpdate, page->pageID(), CoreIPC::In());
+}
+
+void ChunkedUpdateDrawingAreaProxy::didReceiveMessage(CoreIPC::Connection*, CoreIPC::MessageID messageID, CoreIPC::ArgumentDecoder& arguments)
+{
+    switch (messageID.get<DrawingAreaProxyMessage::Kind>()) {
+        case DrawingAreaProxyMessage::Update: {
+            UpdateChunk updateChunk;
+            if (!arguments.decode(updateChunk))
+                return;
+
+            update(&updateChunk);
+            break;
+        }
+        case DrawingAreaProxyMessage::DidSetSize: {
+            UpdateChunk updateChunk;
+            if (!arguments.decode(CoreIPC::Out(updateChunk)))
+                return;
+
+            didSetSize(&updateChunk);
+            break;
+        }
+        default:
+            ASSERT_NOT_REACHED();
+    }
+}
+
+void ChunkedUpdateDrawingAreaProxy::didReceiveSyncMessage(CoreIPC::Connection*, CoreIPC::MessageID, CoreIPC::ArgumentDecoder&, CoreIPC::ArgumentEncoder&)
+{
+    ASSERT_NOT_REACHED();
+}
+
+} // namespace WebKit