Initial PaintInvalidationState support for SVG

Source/core/rendering/PaintInvalidationState.cpp

Index: Source/core/rendering/PaintInvalidationState.cpp
diff --git a/Source/core/rendering/PaintInvalidationState.cpp b/Source/core/rendering/PaintInvalidationState.cpp
index 96a6bf8aaff2808f557b513d6429e600d28d1943..ea23a83849be1b53469ff767b5c31f42f7a1c890 100644
--- a/Source/core/rendering/PaintInvalidationState.cpp
+++ b/Source/core/rendering/PaintInvalidationState.cpp
@@ -9,6 +9,7 @@
 #include "core/rendering/RenderLayer.h"
 #include "core/rendering/RenderView.h"
 #include "core/rendering/svg/RenderSVGModelObject.h"
+#include "core/rendering/svg/RenderSVGRoot.h"
 #include "platform/Partitions.h"
 
 namespace blink {
@@ -76,11 +77,43 @@ PaintInvalidationState::PaintInvalidationState(const PaintInvalidationState& nex
             m_clipRect = next.m_clipRect;
     }
 
+    if (m_cachedOffsetsEnabled && renderer.isSVGRoot()) {
+        const RenderSVGRoot& svgRoot = toRenderSVGRoot(renderer);
+        m_svgTransform = adoptPtr(new AffineTransform(svgRoot.localToBorderBoxTransform()));
+        if (svgRoot.shouldApplyViewportClip())
+            addClipRectRelativeToPaintOffset(svgRoot.pixelSnappedSize());
+    }
+
     applyClipIfNeeded(renderer);
 
     // FIXME: <http://bugs.webkit.org/show_bug.cgi?id=13443> Apply control clip if present.
 }
 
+PaintInvalidationState::PaintInvalidationState(const PaintInvalidationState& next, const RenderSVGModelObject& renderer)
+    : m_clipped(next.m_clipped)
+    , m_cachedOffsetsEnabled(next.m_cachedOffsetsEnabled)
+    , m_forceCheckForPaintInvalidation(next.m_forceCheckForPaintInvalidation)
+    , m_clipRect(next.m_clipRect)
+    , m_paintOffset(next.m_paintOffset)
+    , m_paintInvalidationContainer(next.m_paintInvalidationContainer)
+{
+    ASSERT(renderer != m_paintInvalidationContainer);
+
+    if (m_cachedOffsetsEnabled)
+        m_svgTransform = adoptPtr(new AffineTransform(next.svgTransform() * renderer.localToParentTransform()));
+}
+
+void PaintInvalidationState::addClipRectRelativeToPaintOffset(const LayoutSize& clipSize)
+{
+    LayoutRect clipRect(toPoint(m_paintOffset), clipSize);
+    if (m_clipped) {
+        m_clipRect.intersect(clipRect);
+    } else {
+        m_clipRect = clipRect;
+        m_clipped = true;
+    }
+}
+
 void PaintInvalidationState::applyClipIfNeeded(const RenderObject& renderer)
 {
     if (!renderer.hasOverflowClip())
@@ -90,17 +123,10 @@ void PaintInvalidationState::applyClipIfNeeded(const RenderObject& renderer)
 
     // Do not clip scroll layer contents because the compositor expects the whole layer
     // to be always invalidated in-time.
-    if (box.usesCompositedScrolling()) {
+    if (box.usesCompositedScrolling())
         ASSERT(!m_clipped); // The box should establish paint invalidation container, so no m_clipped inherited.
-    } else {
-        LayoutRect clipRect(toPoint(m_paintOffset), box.layer()->size());
-        if (m_clipped) {
-            m_clipRect.intersect(clipRect);
-        } else {
-            m_clipRect = clipRect;
-            m_clipped = true;
-        }
-    }
+    else
+        addClipRectRelativeToPaintOffset(box.layer()->size());
 
     m_paintOffset -= box.scrolledContentOffset();
 }