[Invalidation Tracking] Add trace events for compositor based invalidations

Source/core/rendering/compositing/CompositingLayerAssigner.cpp

Index: Source/core/rendering/compositing/CompositingLayerAssigner.cpp
diff --git a/Source/core/rendering/compositing/CompositingLayerAssigner.cpp b/Source/core/rendering/compositing/CompositingLayerAssigner.cpp
index f835c9a7e2d28857ee6f3fbd3c56e5c29499c47e..1f3fbb0b875e1041eaf979cdfffa406f5911030e 100644
--- a/Source/core/rendering/compositing/CompositingLayerAssigner.cpp
+++ b/Source/core/rendering/compositing/CompositingLayerAssigner.cpp
@@ -27,6 +27,7 @@
 #include "config.h"
 #include "core/rendering/compositing/CompositingLayerAssigner.h"
 
+#include "core/inspector/InspectorTraceEvents.h"
 #include "core/rendering/compositing/CompositedLayerMapping.h"
 #include "platform/TraceEvent.h"
 
@@ -47,7 +48,7 @@ CompositingLayerAssigner::~CompositingLayerAssigner()
 {
 }
 
-void CompositingLayerAssigner::assign(RenderLayer* updateRoot, Vector<RenderLayer*>& layersNeedingPaintInvalidation)
+void CompositingLayerAssigner::assign(RenderLayer* updateRoot, LayersNeedingPaintInvalidation& layersNeedingPaintInvalidation)
 {
     TRACE_EVENT0("blink", "CompositingLayerAssigner::assign");
 
@@ -172,7 +173,7 @@ CompositingReasons CompositingLayerAssigner::getReasonsPreventingSquashing(const
 }
 
 void CompositingLayerAssigner::updateSquashingAssignment(RenderLayer* layer, SquashingState& squashingState, const CompositingStateTransitionType compositedLayerUpdate,
-    Vector<RenderLayer*>& layersNeedingPaintInvalidation)
+    LayersNeedingPaintInvalidation& layersNeedingPaintInvalidation)
 {
     // NOTE: In the future as we generalize this, the background of this layer may need to be assigned to a different backing than
     // the squashed RenderLayer's own primary contents. This would happen when we have a composited negative z-index element that needs
@@ -195,7 +196,7 @@ void CompositingLayerAssigner::updateSquashingAssignment(RenderLayer* layer, Squ
         layer->clipper().clearClipRectsIncludingDescendants();
 
         // Issue a paint invalidation, since |layer| may have been added to an already-existing squashing layer.
-        layersNeedingPaintInvalidation.append(layer);
+        layersNeedingPaintInvalidation.append(std::make_pair(layer, InspectorLayerInvalidationTrackingEvent::AddedToSquashingLayer));
         m_layersChanged = true;
     } else if (compositedLayerUpdate == RemoveFromSquashingLayer) {
         if (layer->groupedMapping()) {
@@ -206,18 +207,18 @@ void CompositingLayerAssigner::updateSquashingAssignment(RenderLayer* layer, Squ
         }
 
         // If we need to issue paint invalidations, do so now that we've removed it from a squashed layer.
-        layersNeedingPaintInvalidation.append(layer);
+        layersNeedingPaintInvalidation.append(std::make_pair(layer, InspectorLayerInvalidationTrackingEvent::RemovedFromSquashingLayer));
         m_layersChanged = true;
 
         layer->setLostGroupedMapping(false);
     }
 }
 
-void CompositingLayerAssigner::assignLayersToBackingsForReflectionLayer(RenderLayer* reflectionLayer, Vector<RenderLayer*>& layersNeedingPaintInvalidation)
+void CompositingLayerAssigner::assignLayersToBackingsForReflectionLayer(RenderLayer* reflectionLayer, LayersNeedingPaintInvalidation& layersNeedingPaintInvalidation)
 {
     CompositingStateTransitionType compositedLayerUpdate = computeCompositedLayerUpdate(reflectionLayer);
     if (compositedLayerUpdate != NoCompositingStateChange) {
-        layersNeedingPaintInvalidation.append(reflectionLayer);
+        layersNeedingPaintInvalidation.append(std::make_pair(reflectionLayer, InspectorLayerInvalidationTrackingEvent::ReflectionLayerChanged));
         m_layersChanged = true;
         m_compositor->allocateOrClearCompositedLayerMapping(reflectionLayer, compositedLayerUpdate);
     }
@@ -228,7 +229,7 @@ void CompositingLayerAssigner::assignLayersToBackingsForReflectionLayer(RenderLa
         reflectionLayer->compositedLayerMapping()->updateGraphicsLayerConfiguration();
 }
 
-void CompositingLayerAssigner::assignLayersToBackingsInternal(RenderLayer* layer, SquashingState& squashingState, Vector<RenderLayer*>& layersNeedingPaintInvalidation)
+void CompositingLayerAssigner::assignLayersToBackingsInternal(RenderLayer* layer, SquashingState& squashingState, LayersNeedingPaintInvalidation& layersNeedingPaintInvalidation)
 {
     if (m_layerSquashingEnabled && requiresSquashing(layer->compositingReasons())) {
         CompositingReasons reasonsPreventingSquashing = getReasonsPreventingSquashing(layer, squashingState);
@@ -239,7 +240,7 @@ void CompositingLayerAssigner::assignLayersToBackingsInternal(RenderLayer* layer
     CompositingStateTransitionType compositedLayerUpdate = computeCompositedLayerUpdate(layer);
 
     if (m_compositor->allocateOrClearCompositedLayerMapping(layer, compositedLayerUpdate)) {
-        layersNeedingPaintInvalidation.append(layer);
+        layersNeedingPaintInvalidation.append(std::make_pair(layer, InspectorLayerInvalidationTrackingEvent::NewCompositedLayer));
         m_layersChanged = true;
     }