RFR(S): 8240335: C2: assert(found_sfpt) failed: no node in loop that's not input to safepoint

[Roland Westrelin]

Thanks for the reviews and testing.

> Why did you add the check in cfgnode.cpp:1879 which is always true?

It's a leftover from a previous fix attempt. I removed it.

> Please use consistent style in new code:
> - cfgnode.hpp:139: Asterisk position
> - cfgnode.cpp:1781, 1782, 1785: Asterisk position
> - cfgnode.cpp:1786: Loop/whitespace formatting
> - TestCastIIAfterUnrollingInOuterLoop.java:72: Whitespace

I also removed Unique_Node_List::contains() as Vladimir recommended.

http://cr.openjdk.java.net/~roland/8240335/webrev.02/

Roland.