Add a macro for unused trace variables.

src/common/debug.h

@@ -83,6 +83,12 @@ namespace gl
 #define UNUSED_ASSERTION_VARIABLE(variable) ((void)variable)
 #endif
 
+#ifndef ANGLE_ENABLE_TRACE
+#define UNUSED_TRACE_VARIABLE(variable) ((void)variable)
+#else
+#define UNUSED_TRACE_VARIABLE(variable)
+#endif
+
 // A macro to indicate unimplemented functionality
 
 // Define NOASSERT_UNIMPLEMENTED to non zero to skip the assert fail in the unimplemented checks

src/libGLESv2/renderer/d3d11/SwapChain11.cpp

@@ -593,7 +593,7 @@ EGLint SwapChain11::swapRect(EGLint x, EGLint y, EGLint width, EGLint height)
     if (result == DXGI_ERROR_DEVICE_REMOVED)
     {
         HRESULT removedReason = device->GetDeviceRemovedReason();
-        UNUSED_ASSERTION_VARIABLE(removedReason);
+        UNUSED_TRACE_VARIABLE(removedReason);
         ERR("Present failed: the D3D11 device was removed: 0x%08X", removedReason);
         return EGL_CONTEXT_LOST;
     }