Improve support for :read-only and :read-write pseudoclasses.

Source/core/rendering/RenderTheme.cpp

Index: Source/core/rendering/RenderTheme.cpp
diff --git a/Source/core/rendering/RenderTheme.cpp b/Source/core/rendering/RenderTheme.cpp
index 90c56f77dbd6de15b71b66f3e691ca5206b6ffb5..ef230418111c031a424c2ec0a61ad09a7032ab03 100644
--- a/Source/core/rendering/RenderTheme.cpp
+++ b/Source/core/rendering/RenderTheme.cpp
@@ -32,6 +32,7 @@
 #include "core/fileapi/FileList.h"
 #include "core/html/HTMLCollection.h"
 #include "core/html/HTMLDataListElement.h"
+#include "core/html/HTMLFormControlElement.h"
 #include "core/html/HTMLInputElement.h"
 #include "core/html/HTMLMeterElement.h"
 #include "core/html/HTMLOptionElement.h"
@@ -805,9 +806,10 @@ bool RenderTheme::isSpinUpButtonPartPressed(const RenderObject* o) const
 bool RenderTheme::isReadOnlyControl(const RenderObject* o) const
 {
     Node* node = o->node();
-    if (!node || !node->isElementNode())
+    if (!node || !node->isElementNode() || !toElement(node)->isFormControlElement())
         return false;
-    return toElement(node)->matchesReadOnlyPseudoClass();
+    HTMLFormControlElement* element = toHTMLFormControlElement(node);
+    return element->isReadOnly();
 }
 
 bool RenderTheme::isHovered(const RenderObject* o) const