msvcp90: Added basic_streambuf<char> class stub.

dlls/msvcp90/misc.c

@@ -26,10 +26,6 @@
 #include "windef.h"
 #include "winbase.h"
 
-typedef struct {
-    void *mutex;
-} mutex;
-
 /* ??0_Mutex@std@@QAE@XZ */
 /* ??0_Mutex@std@@QEAA@XZ */
 DEFINE_THISCALL_WRAPPER(mutex_ctor, 4)

dlls/msvcp90/msvcp90.h

@@ -22,6 +22,8 @@
 typedef unsigned char MSVCP_bool;
 typedef int MSVCP_long;
 typedef SIZE_T MSVCP_size_t;
+typedef SIZE_T streamoff;
+typedef SIZE_T streamsize;
 
 void __cdecl _invalid_parameter(const wchar_t*, const wchar_t*,
         const wchar_t*, unsigned int, uintptr_t);
@@ -201,3 +203,8 @@ typedef struct {
 
 void init_lockit(void);
 void free_lockit(void);
+
+/* class mutex */
+typedef struct {
+        void *mutex;
+} mutex;