Fixed invalid cast on mingw.

src/ports/SkThread_win.cpp

 
 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include <windows.h>
@@ skipping 18 matching lines @@
                                    static_cast<LONG>(inc));
 }
 
 int32_t sk_atomic_dec(int32_t* addr) {
     return _InterlockedDecrement(reinterpret_cast<LONG*>(addr)) + 1;
 }
 void sk_membar_aquire__after_atomic_dec() { }
 
 int32_t sk_atomic_conditional_inc(int32_t* addr) {
     while (true) {
-        LONG value = static_cast<LONG const volatile&>(*addr);
+        LONG value = static_cast<int32_t const volatile&>(*addr);
         if (value == 0) {
             return 0;
         }
         if (_InterlockedCompareExchange(reinterpret_cast<LONG*>(addr),
                                         value + 1,
                                         value) == value) {
             return value;
         }
     }
 }
@@ skipping 77 matching lines @@
 #pragma const_seg()
 
 #else
 
 #pragma data_seg(".CRT$XLB")
 PIMAGE_TLS_CALLBACK skia_tls_callback = onTLSCallback;
 #pragma data_seg()
 
 #endif
 }