Make setNeedsActiveStyleUpdate mark treescope dirty only.

third_party/WebKit/Source/core/dom/ProcessingInstruction.cpp

Index: third_party/WebKit/Source/core/dom/ProcessingInstruction.cpp
diff --git a/third_party/WebKit/Source/core/dom/ProcessingInstruction.cpp b/third_party/WebKit/Source/core/dom/ProcessingInstruction.cpp
index 051b670bc02913491fdc7248ac1dd30ef43e3f46..60f7095eea393e5c4a4ac8a354811bb15aaf103c 100644
--- a/third_party/WebKit/Source/core/dom/ProcessingInstruction.cpp
+++ b/third_party/WebKit/Source/core/dom/ProcessingInstruction.cpp
@@ -272,20 +272,21 @@ void ProcessingInstruction::removedFrom(ContainerNode* insertionPoint) {
   if (!DocumentXSLT::processingInstructionRemovedFromDocument(document(), this))
     document().styleEngine().removeStyleSheetCandidateNode(*this);
 
-  StyleSheet* removedSheet = m_sheet;
   if (m_sheet) {
     DCHECK_EQ(m_sheet->ownerNode(), this);
     clearSheet();
+    document().styleEngine().setNeedsActiveStyleUpdate(treeScope());
   }
 
   // No need to remove pending sheets.
   clearResource();
 
+  // TODO(rune@opera.com): resolverChanged() can be removed once stylesheet
+  // updates are async. https://crbug.com/567021
   // If we're in document teardown, then we don't need to do any notification of
   // our sheet's removal.
   if (document().isActive())
-    document().styleEngine().setNeedsActiveStyleUpdate(removedSheet,
-                                                       FullStyleUpdate);
+    document().styleEngine().resolverChanged(FullStyleUpdate);
 }
 
 void ProcessingInstruction::clearSheet() {