Simplify HUnaryMathOperation::Canonicalize.

src/arm/lithium-arm.h

Index: src/arm/lithium-arm.h
diff --git a/src/arm/lithium-arm.h b/src/arm/lithium-arm.h
index 91cbc7156c201735515e55e9d7ea88aace3deb18..cee6b858b0b9002c7c7da368453f44de111d3bd4 100644
--- a/src/arm/lithium-arm.h
+++ b/src/arm/lithium-arm.h
@@ -654,6 +654,8 @@ class LDivI V8_FINAL : public LTemplateInstruction<1, 2, 1> {
   LOperand* right() { return inputs_[1]; }
   LOperand* temp() { return temps_[0]; }
 
+  bool is_flooring() { return hydrogen_value()->IsMathFloorOfDiv(); }
+
   DECLARE_CONCRETE_INSTRUCTION(DivI, "div-i")
   DECLARE_HYDROGEN_ACCESSOR(Div)
 };
@@ -2695,7 +2697,6 @@ class LChunkBuilder V8_FINAL : public LChunkBuilderBase {
   LInstruction* DoRSub(HSub* instr);
 
   static bool HasMagicNumberForDivisor(int32_t divisor);
-  static HValue* SimplifiedDivisorForMathFloorOfDiv(HValue* val);
 
   LInstruction* DoMathFloor(HUnaryMathOperation* instr);
   LInstruction* DoMathRound(HUnaryMathOperation* instr);