No bug: Fix comment in mfbt/FastBernoulliTrial.h. DONTBUILD r=me

--HG--
extra : rebase_source : 03a213a8999d4b6b47c6e2be3a8ea06053e24184
extra : amend_source : 9181ae56e72b66bf19fe2129bfab01f0910aaad8

mfbt/FastBernoulliTrial.h

@@ -240,7 +240,7 @@ class FastBernoulliTrial {
        * we say something "equals 1", that means it's exactly equal to 1. We
        * treat approximation using intervals with open boundaries: saying a
        * value is in (0,1) doesn't specify how close to 0 or 1 the value gets.
-       * When we use closed boundaries like [1, 2**-53], we're careful to ensure
+       * When we use closed boundaries like [2**-53, 1], we're careful to ensure
        * the boundary values are actually representable.)
        *
        * - After the comparison above, we know mProbability is in (0,1).