Make ExceptionCode be an enum that does not encode the "code" property

Source/core/dom/DOMCoreException.h

Index: Source/core/dom/DOMCoreException.h
diff --git a/Source/core/dom/DOMCoreException.h b/Source/core/dom/DOMCoreException.h
index 1a98c6e4b091d1d846d4e0eb29185743ca578fa0..77a94d1f7e8121016c9ed2733871499346d61420 100644
--- a/Source/core/dom/DOMCoreException.h
+++ b/Source/core/dom/DOMCoreException.h
@@ -34,6 +34,40 @@
 
 namespace WebCore {
 
+// FIXME: This should be private once IDBDatabaseException is gone.
+enum {
+    IndexSizeErrorLegacyCode = 1,
+    HierarchyRequestErrorLegacyCode = 3,
+    WrongDocumentErrorLegacyCode = 4,
+    InvalidCharacterErrorLegacyCode = 5,
+    NoModificationAllowedErrorLegacyCode = 7,
+    NotFoundErrorLegacyCode = 8,
+    NotSupportedErrorLegacyCode = 9,
+    InuseAttributeErrorLegacyCode = 10, // Historical. Only used in setAttributeNode etc which have been removed from the DOM specs.
+
+    // Introduced in DOM Level 2:
+    InvalidStateErrorLegacyCode = 11,
+    SyntaxErrorLegacyCode = 12,
+    InvalidModificationErrorLegacyCode = 13,
+    NamespaceErrorLegacyCode = 14,
+    InvalidAccessErrorLegacyCode = 15,
+
+    // Introduced in DOM Level 3:
+    TypeMismatchErrorLegacyCode = 17, // Historical; use TypeError instead
+
+    // XMLHttpRequest extension:
+    SecurityErrorLegacyCode = 18,
+
+    // Others introduced in HTML5:
+    NetworkErrorLegacyCode = 19,
+    AbortErrorLegacyCode = 20,
+    UrlMismatchErrorLegacyCode = 21,
+    QuotaExceededErrorLegacyCode = 22,
+    TimeoutErrorLegacyCode = 23,
+    InvalidNodeTypeErrorLegacyCode = 24,
+    DataCloneErrorLegacyCode = 25
+};
+
 class DOMCoreException : public ExceptionBase, public ScriptWrappable {
 public:
     static PassRefPtr<DOMCoreException> create(const ExceptionCodeDescription& description)
@@ -42,6 +76,7 @@ public:
     }
 
     static bool initializeDescription(ExceptionCode, ExceptionCodeDescription*);
+    static int getLegacyErrorCode(ExceptionCode);
 
 private:
     explicit DOMCoreException(const ExceptionCodeDescription& description)