Removing a RenderLayer's CLM should trigger a repaint

This makes RLC::applyUpdateLayerCompositingStateChickenEggHacks issue a repaint when a RenderLayer gains or loses a CLM. Review URL: https://codereview.chromium.org/336493004 git-svn-id: svn://svn.chromium.org/blink/trunk@176128 bbb929c8-8fbe-4397-9dbb-9b2b20218538

Removing a RenderLayer's CLM should trigger a repaint
This makes RLC::applyUpdateLayerCompositingStateChickenEggHacks issue a repaint when a RenderLayer gains or loses a CLM. Review URL: https://codereview.chromium.org/336493004 git-svn-id: svn://svn.chromium.org/blink/trunk@176128 bbb929c8-8fbe-4397-9dbb-9b2b20218538
7dc5fd18 · ajuma@chromium.org · d64d3af4 · 7dc5fd18 · 7dc5fd18 · 7dc5fd18
Commit 7dc5fd18 authored Jun 13, 2014 by ajuma@chromium.org
4 changed files
--- a/third_party/WebKit/LayoutTests/compositing/layer-creation/compositing-reason-removed-expected.txt
+++ b/third_party/WebKit/LayoutTests/compositing/layer-creation/compositing-reason-removed-expected.txt
+(GraphicsLayer
+  (bounds 800.00 600.00)
+  (children 1
+    (GraphicsLayer
+      (bounds 800.00 600.00)
+      (contentsOpaque 1)
+      (drawsContent 1)
+      (repaint rects
+        (rect 8.00 8.00 30.00 30.00)
+      )
+    )
+  )
+)
+
--- a/third_party/WebKit/LayoutTests/compositing/layer-creation/compositing-reason-removed.html
+++ b/third_party/WebKit/LayoutTests/compositing/layer-creation/compositing-reason-removed.html
+<!DOCTYPE html>
+<style>
+  #square {
+    background-color: blue;
+    width: 30px;
+    height: 30px;
+    position: relative;
+    -webkit-backface-visibility: hidden;
+  }
+
+  #testResults {
+    display: none;
+  }
+</style>
+
+<script>
+  if (window.testRunner) {
+    testRunner.dumpAsText();
+  }
+
+  onload = function() {
+    if (!window.internals)
+      return;
+
+    window.internals.startTrackingRepaints(document);
+
+    // Remove the div's only compositing reason. This should trigger a repaint.
+    document.getElementById("square").style.webkitBackfaceVisibility = "visible";
+    document.getElementById("layertree").textContent = window.internals.layerTreeAsText(document, internals.LAYER_TREE_INCLUDES_REPAINT_RECTS);
+    window.internals.stopTrackingRepaints(document);
+
+    document.getElementById("testResults").style.display = "block";
+  }
+</script>
+
+<div id="square"></div>
+
+<div id="testResults">
+  <pre id="layertree"></pre>
+</div>
--- a/third_party/WebKit/LayoutTests/compositing/squashing/squashed-layer-loses-graphicslayer-expected.txt
+++ b/third_party/WebKit/LayoutTests/compositing/squashing/squashed-layer-loses-graphicslayer-expected.txt
@@ -42,6 +42,7 @@ CASE 2, The original composited layer is no longer composited, which then also r
        (rect 220.00 220.00 100.00 100.00)
        (rect 140.00 140.00 100.00 100.00)
        (rect 60.00 60.00 100.00 100.00)
+        (rect 60.00 60.00 100.00 100.00)
      )
    )
  )

--- a/third_party/WebKit/Source/core/rendering/compositing/RenderLayerCompositor.cpp
+++ b/third_party/WebKit/Source/core/rendering/compositing/RenderLayerCompositor.cpp
@@ -474,8 +474,19 @@ bool RenderLayerCompositor::updateLayerIfViewportConstrained(RenderLayer* layer)
 // See crbug.com/383191 for a list of tests that fail if this method is removed.
 void RenderLayerCompositor::applyUpdateLayerCompositingStateChickenEggHacks(RenderLayer* layer, CompositingStateTransitionType compositedLayerUpdate)
 {
-    if (compositedLayerUpdate != NoCompositingStateChange)
-        allocateOrClearCompositedLayerMapping(layer, compositedLayerUpdate);
+    if (compositedLayerUpdate != NoCompositingStateChange) {
+        bool compositedLayerMappingChanged = allocateOrClearCompositedLayerMapping(layer, compositedLayerUpdate);
+        if (compositedLayerMappingChanged) {
+            // Repaint rects can only be computed for layers that have already been attached to the
+            // render tree, but a chicken-egg compositing update can happen before |layer| gets
+            // attached. Since newly-created renderers don't get parented until they are attached
+            // (see RenderTreeBuilder::createRendererForElementIfNeeded), we can check for attachment
+            // by checking for a parent.
+            if (layer->parent())
+                layer->repainter().computeRepaintRectsIncludingNonCompositingDescendants();
+            repaintOnCompositingChange(layer);
+        }
+    }
 }

 void RenderLayerCompositor::updateLayerCompositingState(RenderLayer* layer, UpdateLayerCompositingStateOptions options)