[assembler] Remove unnecessary cast.

src/arm/assembler-arm-inl.h

Index: src/arm/assembler-arm-inl.h
diff --git a/src/arm/assembler-arm-inl.h b/src/arm/assembler-arm-inl.h
index c99331c0a8bf948d3137f5e200aa3f80d6358b76..661895d82592973a7575da4f8722b00ae0abd250 100644
--- a/src/arm/assembler-arm-inl.h
+++ b/src/arm/assembler-arm-inl.h
@@ -219,9 +219,9 @@ void RelocInfo::set_debug_call_address(Address target) {
   Memory::Address_at(pc_ + Assembler::kPatchDebugBreakSlotAddressOffset) =
       target;
   if (host() != NULL) {
-    Object* target_code = Code::GetCodeFromTargetAddress(target);
-    host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(
-        host(), this, HeapObject::cast(target_code));
+    Code* target_code = Code::GetCodeFromTargetAddress(target);
+    host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(host(), this,
+                                                                  target_code);
   }
 }