[turbofan] Add the TruncateFloat32ToInt32 operator to turbofan.

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

Index: src/compiler/arm/instruction-selector-arm.cc
diff --git a/src/compiler/arm/instruction-selector-arm.cc b/src/compiler/arm/instruction-selector-arm.cc
index f3deae7d758f0eee1ecd13ce0c766d7e3146628f..511c25b350e81384f659656461031301d06fdb44 100644
--- a/src/compiler/arm/instruction-selector-arm.cc
+++ b/src/compiler/arm/instruction-selector-arm.cc
@@ -931,6 +931,11 @@ void InstructionSelector::VisitChangeUint32ToFloat64(Node* node) {
 }
 
 
+void InstructionSelector::VisitTruncateFloat32ToInt32(Node* node) {
+  VisitRR(this, kArmVcvtS32F32, node);
+}
+
+
 void InstructionSelector::VisitChangeFloat64ToInt32(Node* node) {
   VisitRR(this, kArmVcvtS32F64, node);
 }