Revert 84197 - Add one-time randomization support for FieldTrial, and the ability to

base/rand_util.cc

Index: base/rand_util.cc
===================================================================
--- base/rand_util.cc	(revision 84367)
+++ base/rand_util.cc	(working copy)
@@ -25,10 +25,6 @@
 }
 
 double RandDouble() {
-  return BitsToOpenEndedUnitInterval(base::RandUint64());
-}
-
-double BitsToOpenEndedUnitInterval(uint64 bits) {
   // We try to get maximum precision by masking out as many bits as will fit
   // in the target type's mantissa, and raising it to an appropriate power to
   // produce output in the range [0, 1).  For IEEE 754 doubles, the mantissa
@@ -36,7 +32,7 @@
 
   COMPILE_ASSERT(std::numeric_limits<double>::radix == 2, otherwise_use_scalbn);
   static const int kBits = std::numeric_limits<double>::digits;
-  uint64 random_bits = bits & ((GG_UINT64_C(1) << kBits) - 1);
+  uint64 random_bits = base::RandUint64() & ((GG_UINT64_C(1) << kBits) - 1);
   double result = ldexp(static_cast<double>(random_bits), -1 * kBits);
   DCHECK_GE(result, 0.0);
   DCHECK_LT(result, 1.0);