[DOM4] Have ProcessingInstruction inherit CharacterData

Source/core/dom/CharacterData.cpp

Index: Source/core/dom/CharacterData.cpp
diff --git a/Source/core/dom/CharacterData.cpp b/Source/core/dom/CharacterData.cpp
index 7221496f8eb32eacd44106b045a96c7898da9108..e132ba5d1238ace6d9177e2e4dcb171ac9ac9f9e 100644
--- a/Source/core/dom/CharacterData.cpp
+++ b/Source/core/dom/CharacterData.cpp
@@ -29,6 +29,7 @@
 #include "core/dom/MutationEvent.h"
 #include "core/dom/MutationObserverInterestGroup.h"
 #include "core/dom/MutationRecord.h"
+#include "core/dom/ProcessingInstruction.h"
 #include "core/dom/Text.h"
 #include "core/editing/FrameSelection.h"
 #include "core/inspector/InspectorInstrumentation.h"
@@ -200,6 +201,9 @@ void CharacterData::setDataAndUpdate(const String& newData, unsigned offsetOfRep
     if (isTextNode())
         toText(this)->updateTextRenderer(offsetOfReplacedData, oldLength);
 
+    if (nodeType() == PROCESSING_INSTRUCTION_NODE)
+        toProcessingInstruction(this)->checkStyleSheet();
+
     if (document()->frame())
         document()->frame()->selection()->textWasReplaced(this, offsetOfReplacedData, oldLength, newLength);