operator>> behavior changed slightly so that the stream is not accessed when unrecognized character sequence is detected.

[SVN r67184]

libs/optional

@@ -1 +1 @@
-Subproject commit 64d8062621d07f390482968927d2e0a415280b2c
+Subproject commit 646488e0e2f87e5e77d2e764ce642db2304e9ec0