Merge WebKit at r78450: Initial merge by git.

Change-Id: I6d3e5f1f868ec266a0aafdef66182ddc3f265dc1

1 files changed, 103 insertions, 4 deletions

diff --git a/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.cpp b/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.cpp
index 3207094..6a65841 100644
--- a/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.cpp
+++ b/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.cpp
@@ -23,15 +23,18 @@
  * THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include "config.h"
 #include "DrawingAreaProxyImpl.h"
 
 #include "DrawingAreaMessages.h"
+#include "DrawingAreaProxyMessages.h"
+#include "LayerTreeContext.h"
 #include "Region.h"
 #include "UpdateInfo.h"
 #include "WebPageProxy.h"
 #include "WebProcessProxy.h"
 
-#ifndef __APPLE__
+#if !PLATFORM(MAC) && !PLATFORM(WIN)
 #error "This drawing area is not ready for use by other ports yet."
 #endif
 
@@ -47,11 +50,15 @@ PassOwnPtr<DrawingAreaProxyImpl> DrawingAreaProxyImpl::create(WebPageProxy* webP
 DrawingAreaProxyImpl::DrawingAreaProxyImpl(WebPageProxy* webPageProxy)
     : DrawingAreaProxy(DrawingAreaInfo::Impl, webPageProxy)
     , m_isWaitingForDidSetSize(false)
+    , m_lastDidSetSizeSequenceNumber(0)
 {
 }
 
 DrawingAreaProxyImpl::~DrawingAreaProxyImpl()
 {
+    // Make sure to exit accelerated compositing mode.
+    if (isInAcceleratedCompositingMode())
+        exitAcceleratedCompositingMode();
 }
 
 void DrawingAreaProxyImpl::paint(BackingStore::PlatformGraphicsContext context, const IntRect& rect, Region& unpaintedRegion)
@@ -61,6 +68,18 @@ void DrawingAreaProxyImpl::paint(BackingStore::PlatformGraphicsContext context,
     if (!m_backingStore)
         return;
 
+    ASSERT(!isInAcceleratedCompositingMode());
+
+    if (m_isWaitingForDidSetSize) {
+        // Wait for a DidSetSize message that contains the new bits before we paint
+        // what's currently in the backing store.
+        waitForAndDispatchDidSetSize();
+
+        // Dispatching DidSetSize could destroy our backing store or change the compositing mode.
+        if (!m_backingStore || isInAcceleratedCompositingMode())
+            return;
+    }
+
     m_backingStore->paint(context, rect);
     unpaintedRegion.subtract(IntRect(IntPoint(), m_backingStore->size()));
 }
@@ -112,29 +131,71 @@ void DrawingAreaProxyImpl::detachCompositingContext()
     ASSERT_NOT_REACHED();
 }
 
-void DrawingAreaProxyImpl::update(const UpdateInfo& updateInfo)
+void DrawingAreaProxyImpl::update(uint64_t sequenceNumber, const UpdateInfo& updateInfo)
 {
+    if (sequenceNumber < m_lastDidSetSizeSequenceNumber)
+        return;
+
     // FIXME: Handle the case where the view is hidden.
 
     incorporateUpdate(updateInfo);
     m_webPageProxy->process()->send(Messages::DrawingArea::DidUpdate(), m_webPageProxy->pageID());
 }
 
-void DrawingAreaProxyImpl::didSetSize(const UpdateInfo& updateInfo)
+void DrawingAreaProxyImpl::didSetSize(uint64_t sequenceNumber, const UpdateInfo& updateInfo, const LayerTreeContext& layerTreeContext)
 {
+    ASSERT(sequenceNumber > m_lastDidSetSizeSequenceNumber);
+    m_lastDidSetSizeSequenceNumber = sequenceNumber;
+
     ASSERT(m_isWaitingForDidSetSize);
     m_isWaitingForDidSetSize = false;
 
     if (m_size != updateInfo.viewSize)
         sendSetSize();
 
+    if (layerTreeContext != m_layerTreeContext) {
+        if (!m_layerTreeContext.isEmpty()) {
+            exitAcceleratedCompositingMode();
+            ASSERT(m_layerTreeContext.isEmpty());
+        }
+
+        if (!layerTreeContext.isEmpty()) {
+            enterAcceleratedCompositingMode(layerTreeContext);
+            ASSERT(layerTreeContext == m_layerTreeContext);
+        }            
+    }
+
+    if (isInAcceleratedCompositingMode()) {
+        ASSERT(!m_backingStore);
+        return;
+    }
+
     m_backingStore = nullptr;
+    incorporateUpdate(updateInfo);
+}
+
+void DrawingAreaProxyImpl::enterAcceleratedCompositingMode(uint64_t sequenceNumber, const LayerTreeContext& layerTreeContext)
+{
+    if (sequenceNumber < m_lastDidSetSizeSequenceNumber)
+        return;
+
+    enterAcceleratedCompositingMode(layerTreeContext);
+}
+
+void DrawingAreaProxyImpl::exitAcceleratedCompositingMode(uint64_t sequenceNumber, const UpdateInfo& updateInfo)
+{
+    if (sequenceNumber < m_lastDidSetSizeSequenceNumber)
+        return;
+
+    exitAcceleratedCompositingMode();
 
     incorporateUpdate(updateInfo);
 }
 
 void DrawingAreaProxyImpl::incorporateUpdate(const UpdateInfo& updateInfo)
 {
+    ASSERT(!isInAcceleratedCompositingMode());
+
     if (updateInfo.updateRectBounds.isEmpty())
         return;
 
@@ -164,7 +225,45 @@ void DrawingAreaProxyImpl::sendSetSize()
         return;
 
     m_isWaitingForDidSetSize = true;
-    m_webPageProxy->process()->send(Messages::DrawingArea::SetSize(m_size), m_webPageProxy->pageID());
+    m_webPageProxy->process()->send(Messages::DrawingArea::SetSize(m_size, m_scrollOffset), m_webPageProxy->pageID());
+    m_scrollOffset = IntSize();
+
+    if (!m_layerTreeContext.isEmpty()) {
+        // Wait for the DidSetSize message. Normally we don this in DrawingAreaProxyImpl::paint, but that
+        // function is never called when in accelerated compositing mode.
+        waitForAndDispatchDidSetSize();
+    }
+}
+
+void DrawingAreaProxyImpl::waitForAndDispatchDidSetSize()
+{
+    ASSERT(m_isWaitingForDidSetSize);
+
+    if (!m_webPageProxy->isValid())
+        return;
+    if (m_webPageProxy->process()->isLaunching())
+        return;
+    
+    // The timeout, in seconds, we use when waiting for a DidSetSize message when we're asked to paint.
+    static const double didSetSizeTimeout = 0.5;
+    m_webPageProxy->process()->connection()->waitForAndDispatchImmediately<Messages::DrawingAreaProxy::DidSetSize>(m_webPageProxy->pageID(), didSetSizeTimeout);
+}
+
+void DrawingAreaProxyImpl::enterAcceleratedCompositingMode(const LayerTreeContext& layerTreeContext)
+{
+    ASSERT(!isInAcceleratedCompositingMode());
+
+    m_backingStore = nullptr;
+    m_layerTreeContext = layerTreeContext;
+    m_webPageProxy->enterAcceleratedCompositingMode(layerTreeContext);
+}
+
+void DrawingAreaProxyImpl::exitAcceleratedCompositingMode()
+{
+    ASSERT(isInAcceleratedCompositingMode());
+
+    m_layerTreeContext = LayerTreeContext();    
+    m_webPageProxy->exitAcceleratedCompositingMode();
 }
 
 } // namespace WebKit