(NOT FOR COMMIT) Testing layer invalidation speedups.

third_party/WebKit/Source/platform/graphics/GraphicsLayer.cpp

Index: third_party/WebKit/Source/platform/graphics/GraphicsLayer.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/GraphicsLayer.cpp b/third_party/WebKit/Source/platform/graphics/GraphicsLayer.cpp
index a95334c4641afdfbdad83a6da2c60e3f72df8c38..f48542c3331097de61199d541f41a5eddb74478d 100644
--- a/third_party/WebKit/Source/platform/graphics/GraphicsLayer.cpp
+++ b/third_party/WebKit/Source/platform/graphics/GraphicsLayer.cpp
@@ -1057,19 +1057,39 @@ void GraphicsLayer::setNeedsDisplay()
         trackPaintInvalidation(*this, FloatRect(FloatPoint(), m_size), PaintInvalidationFull);
 }
 
-void GraphicsLayer::setNeedsDisplayInRect(const IntRect& rect, PaintInvalidationReason invalidationReason, const DisplayItemClient& client)
+void GraphicsLayer::setNeedsDisplayInRect(const Vector<NeedsDisplayRecord>& rects)
 {
     if (!drawsContent())
         return;
 
-    m_layer->layer()->invalidateRect(rect);
-    if (firstPaintInvalidationTrackingEnabled())
-        m_debugInfo.appendAnnotatedInvalidateRect(rect, invalidationReason);
+    std::vector<blink::WebRect> offsetRects(rects.size());
+
+    for (size_t i = 0; i < rects.size(); ++i) {
+        IntRect rect = rects[i].r;
+        rect.move(-offsetFromLayoutObject());
+        offsetRects[i] = rect;
+    }
+
+    m_layer->layer()->invalidateRects(offsetRects);
+
+    if (firstPaintInvalidationTrackingEnabled()) {
+        for (size_t i = 0; i < rects.size(); ++i) {
+            IntRect rect = rects[i].r;
+            rect.move(-offsetFromLayoutObject());
+            m_debugInfo.appendAnnotatedInvalidateRect(rect, rects[i].invalidationReason);
+        }
+    }
+
     for (size_t i = 0; i < m_linkHighlights.size(); ++i)
         m_linkHighlights[i]->invalidate();
 
-    if (isTrackingPaintInvalidations())
-        trackPaintInvalidation(client, rect, invalidationReason);
+    if (isTrackingPaintInvalidations()) {
+        for (size_t i = 0; i < rects.size(); ++i) {
+            IntRect rect = rects[i].r;
+            rect.move(-offsetFromLayoutObject());
+            trackPaintInvalidation(rects[i].client, rect, rects[i].invalidationReason);
+        }
+    }
 }
 
 void GraphicsLayer::invalidateDisplayItemClient(const DisplayItemClient& displayItemClient, PaintInvalidationReason invalidationReason)