Ignore overflow clip on root layer if HitTestRequest::IgnoreClipping is set.

Source/core/paint/DeprecatedPaintLayer.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 1708 matching lines @@
 //  *zOffset on return is the z offset of the hit point relative to the containing flattening layer.
 DeprecatedPaintLayer* DeprecatedPaintLayer::hitTestLayer(DeprecatedPaintLayer* rootLayer, DeprecatedPaintLayer* containerLayer, HitTestResult& result,
     const LayoutRect& hitTestRect, const HitTestLocation& hitTestLocation, bool appliedTransform,
     const HitTestingTransformState* transformState, double* zOffset)
 {
     ASSERT(layoutObject()->document().lifecycle().state() >= DocumentLifecycle::CompositingClean);
 
     if (!isSelfPaintingLayer() && !hasSelfPaintingLayerDescendant())
         return 0;
 
-    // The natural thing would be to keep HitTestingTransformState on the stack, but it's big, so we heap-allocate.
+    ClipRectsCacheSlot clipRectsCacheSlot = result.hitTestRequest().ignoreClipping() ? RootRelativeClipRectsIgnoringViewportClip : RootRelativeClipRects;
 
     // Apply a transform if we have one.
     if (transform() && !appliedTransform) {
         if (enclosingPaginationLayer())
-            return hitTestTransformedLayerInFragments(rootLayer, containerLayer, result, hitTestRect, hitTestLocation, transformState, zOffset);
+            return hitTestTransformedLayerInFragments(rootLayer, containerLayer, result, hitTestRect, hitTestLocation, transformState, zOffset, clipRectsCacheSlot);
 
         // Make sure the parent's clip rects have been calculated.
         if (parent()) {
-            ClipRect clipRect = clipper().backgroundClipRect(ClipRectsContext(rootLayer, RootRelativeClipRects, IncludeOverlayScrollbarSize));
+            ClipRect clipRect = clipper().backgroundClipRect(ClipRectsContext(rootLayer, clipRectsCacheSlot, IncludeOverlayScrollbarSize));
             // Go ahead and test the enclosing clip now.
             if (!clipRect.intersects(hitTestLocation))
                 return 0;
         }
 
         return hitTestLayerByApplyingTransform(rootLayer, containerLayer, result, hitTestRect, hitTestLocation, transformState, zOffset);
     }
 
     // Ensure our lists and 3d status are up-to-date.
     m_stackingNode->updateLayerListsIfNeeded();
     update3DTransformedDescendantStatus();
 
+    // The natural thing would be to keep HitTestingTransformState on the stack, but it's big, so we heap-allocate.
     RefPtr<HitTestingTransformState> localTransformState;
     if (appliedTransform) {
         // We computed the correct state in the caller (above code), so just reference it.
         ASSERT(transformState);
         localTransformState = const_cast<HitTestingTransformState*>(transformState);
     } else if (transformState || m_has3DTransformedDescendant || preserves3D()) {
         // We need transform state for the first time, or to offset the container state, so create it here.
         localTransformState = createLocalTransformState(rootLayer, containerLayer, hitTestRect, hitTestLocation, transformState);
     }
 
@@ skipping 48 matching lines @@
         localTransformState.get(), zOffsetForDescendantsPtr, zOffset, unflattenedTransformState.get(), depthSortDescendants);
     if (hitLayer) {
         if (!depthSortDescendants)
             return hitLayer;
         candidateLayer = hitLayer;
     }
 
     // Collect the fragments. This will compute the clip rectangles for each layer fragment.
     DeprecatedPaintLayerFragments layerFragments;
     if (appliedTransform)
-        appendSingleFragmentIgnoringPagination(layerFragments, rootLayer, hitTestRect, RootRelativeClipRects, IncludeOverlayScrollbarSize);
+        appendSingleFragmentIgnoringPagination(layerFragments, rootLayer, hitTestRect, clipRectsCacheSlot, IncludeOverlayScrollbarSize);
     else
-        collectFragments(layerFragments, rootLayer, hitTestRect, RootRelativeClipRects, IncludeOverlayScrollbarSize);
+        collectFragments(layerFragments, rootLayer, hitTestRect, clipRectsCacheSlot, IncludeOverlayScrollbarSize);
 
     if (m_scrollableArea && m_scrollableArea->hitTestResizerInFragments(layerFragments, hitTestLocation)) {
         layoutObject()->updateHitTestResult(result, hitTestLocation.point());
         return this;
     }
 
     // Next we want to see if the mouse pos is inside the child LayoutObjects of the layer. Check
     // every fragment in reverse order.
     if (isSelfPaintingLayer()) {
         // Hit test with a temporary HitTestResult, because we only want to commit to 'result' if we know we're frontmost.
@@ skipping 58 matching lines @@
             continue;
         insideClipRect = true;
         if (hitTestContents(result, fragment.layerBounds, hitTestLocation, hitTestFilter))
             return true;
     }
 
     return false;
 }
 
 DeprecatedPaintLayer* DeprecatedPaintLayer::hitTestTransformedLayerInFragments(DeprecatedPaintLayer* rootLayer, DeprecatedPaintLayer* containerLayer, HitTestResult& result,
-    const LayoutRect& hitTestRect, const HitTestLocation& hitTestLocation, const HitTestingTransformState* transformState, double* zOffset)
+    const LayoutRect& hitTestRect, const HitTestLocation& hitTestLocation, const HitTestingTransformState* transformState, double* zOffset, ClipRectsCacheSlot clipRectsCacheSlot)
 {
     DeprecatedPaintLayerFragments enclosingPaginationFragments;
     LayoutPoint offsetOfPaginationLayerFromRoot;
     // FIXME: We're missing a sub-pixel offset here crbug.com/348728
     LayoutRect transformedExtent = transparencyClipBox(this, enclosingPaginationLayer(), HitTestingTransparencyClipBox, DeprecatedPaintLayer::RootOfTransparencyClipBox, LayoutSize());
     enclosingPaginationLayer()->collectFragments(enclosingPaginationFragments, rootLayer, hitTestRect,
-        RootRelativeClipRects, IncludeOverlayScrollbarSize, RespectOverflowClip, &offsetOfPaginationLayerFromRoot, LayoutSize(), &transformedExtent);
+        clipRectsCacheSlot, IncludeOverlayScrollbarSize, RespectOverflowClip, &offsetOfPaginationLayerFromRoot, LayoutSize(), &transformedExtent);
 
     for (int i = enclosingPaginationFragments.size() - 1; i >= 0; --i) {
         const DeprecatedPaintLayerFragment& fragment = enclosingPaginationFragments.at(i);
 
         // Apply the page/column clip for this fragment, as well as any clips established by layers in between us and
         // the enclosing pagination layer.
         LayoutRect clipRect = fragment.backgroundRect.rect();
 
         // Now compute the clips within a given fragment
         if (parent() != enclosingPaginationLayer()) {
             enclosingPaginationLayer()->convertToLayerCoords(rootLayer, offsetOfPaginationLayerFromRoot);
-            LayoutRect parentClipRect = clipper().backgroundClipRect(ClipRectsContext(enclosingPaginationLayer(), RootRelativeClipRects, IncludeOverlayScrollbarSize)).rect();
+            LayoutRect parentClipRect = clipper().backgroundClipRect(ClipRectsContext(enclosingPaginationLayer(), clipRectsCacheSlot, IncludeOverlayScrollbarSize)).rect();
             parentClipRect.moveBy(fragment.paginationOffset + offsetOfPaginationLayerFromRoot);
             clipRect.intersect(parentClipRect);
         }
 
         if (!hitTestLocation.intersects(clipRect))
             continue;
 
         DeprecatedPaintLayer* hitLayer = hitTestLayerByApplyingTransform(rootLayer, containerLayer, result, hitTestRect, hitTestLocation,
             transformState, zOffset, fragment.paginationOffset);
         if (hitLayer)
@@ skipping 833 matching lines @@
 
 void showLayerTree(const blink::LayoutObject* layoutObject)
 {
     if (!layoutObject) {
         fprintf(stderr, "Cannot showLayerTree. Root is (nil)\n");
         return;
     }
     showLayerTree(layoutObject->enclosingLayer());
 }
 #endif