[turbofan] Float32Abs and Float64Abs are supported by all backends.

src/compiler/arm/instruction-selector-arm.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/base/adapters.h"
 #include "src/base/bits.h"
 #include "src/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties.h"
 
@@ skipping 1576 matching lines @@
   }
   Emit(kArmVmovHighF64U32, g.DefineSameAsFirst(node), g.UseRegister(left),
        g.UseRegister(right));
 }
 
 
 // static
 MachineOperatorBuilder::Flags
 InstructionSelector::SupportedMachineOperatorFlags() {
   MachineOperatorBuilder::Flags flags =
-      MachineOperatorBuilder::kFloat32Abs |
-      MachineOperatorBuilder::kFloat64Abs |
       MachineOperatorBuilder::kInt32DivIsSafe |
       MachineOperatorBuilder::kUint32DivIsSafe;
-
   if (CpuFeatures::IsSupported(ARMv8)) {
     flags |= MachineOperatorBuilder::kFloat64RoundDown |
              MachineOperatorBuilder::kFloat64RoundTruncate |
              MachineOperatorBuilder::kFloat64RoundTiesAway;
   }
   return flags;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8