Remove duplicated headers from modules/ directory

Source/modules/indexeddb/IDBCursor.h

Index: Source/modules/indexeddb/IDBCursor.h
diff --git a/Source/modules/indexeddb/IDBCursor.h b/Source/modules/indexeddb/IDBCursor.h
index d45455b4bc3e9cc08dabe4d481b5ddcaa4932f8a..e216217a517483e5b3b82e0d9d15e74e6782152c 100644
--- a/Source/modules/indexeddb/IDBCursor.h
+++ b/Source/modules/indexeddb/IDBCursor.h
@@ -30,7 +30,6 @@
 #include "bindings/v8/ScriptWrappable.h"
 #include "modules/indexeddb/IDBKey.h"
 #include "modules/indexeddb/IDBRequest.h"
-#include "modules/indexeddb/IDBTransaction.h"

[Nico, 2013/12/09 02:01:27]

Isn't this needed since there's a RefPtr<IDBTransaction> below (which requires
availability of AddRef of its template argument at instantiation time)?

[Inactive, 2013/12/10 20:26:19]

AFAIK, a forward declaration is sufficient for T despite having a RefPtr<T>
member in the header, as long as that member is not used in the header.

If the ~IDBCursor() destructor were omitted, or if it was defined in the header
(not just declared), then the code would not build with a simple forward
declaration. However, in this case, the destructor is defined in the cpp and
IDBTransaction.h is included from the cpp so it should be fine.

 #include "modules/indexeddb/IndexedDB.h"
 #include "public/platform/WebIDBCursor.h"
 #include "wtf/PassRefPtr.h"
@@ -42,6 +41,7 @@ namespace WebCore {
 class DOMRequestState;
 class ExceptionState;
 class IDBAny;
+class IDBTransaction;
 class ExecutionContext;
 class SharedBuffer;