mesa: return early if mask is cleared to zero in BlitFramebuffer
From ARB_framebuffer_object:
If a buffer is specified in <mask> and does not exist in both the
read and draw framebuffers, the corresponding bit is silently
ignored.
diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
index d094dd3..8496936 100644
--- a/src/mesa/main/fbobject.c
+++ b/src/mesa/main/fbobject.c
@@ -2603,6 +2603,10 @@
}
}
+ if (!mask) {
+ return;
+ }
+
ASSERT(ctx->Driver.BlitFramebuffer);
ctx->Driver.BlitFramebuffer(ctx,
srcX0, srcY0, srcX1, srcY1,