Add benchmark for BaseEncoding.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81099316
Steer some consistentHash users to WeightedConsistentHash.
Steer all weightedConsistentHash users to WeightedConsistentHash.

(WeightedConsistentHash is internal only at this point.)
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81155544
Fixed isAssignableFrom() for <? super T> wildcard types, as pointed out by Guava issue 1898.

In a nutshell, here's what we have in the current implementation:

List<? super String>.isAssignableFrom(List<Object>) == true // Correct
<? super CharSequence>.isAssignableFrom(String) == false // Wrong!
<? super String>.isAssignableFrom(<Object>) == true // Wrong! Not assignable

To show why they are wrong, consider the following three code snippets where the first two compile and the third doesn't compile:

void okay(Receiver<List<? super String>> receiver, List<Object> objects) {
receiver.accept(objects);
}

void okay2(Receiver<? super CharSequence> receiver) {
receiver.accept("1");
}

void notOkay(Receiver<? super String> receiver, Object obj) {
receiver.accept(obj);
}
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81180102
Delete AsyncSettableFuture.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81197333
Rewrite nonCancellationPropagating to take advantage of setFuture
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81244943