[assembler] Remove unnecessary cast.

src/arm/assembler-arm-inl.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
 // are met:
 //
 // - Redistributions of source code must retain the above copyright notice,
 // this list of conditions and the following disclaimer.
 //
@@ skipping 201 matching lines @@
   DCHECK(IsDebugBreakSlot(rmode()) && IsPatchedDebugBreakSlotSequence());
   return Memory::Address_at(pc_ + Assembler::kPatchDebugBreakSlotAddressOffset);
 }
 
 
 void RelocInfo::set_debug_call_address(Address target) {
   DCHECK(IsDebugBreakSlot(rmode()) && IsPatchedDebugBreakSlotSequence());
   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);
   }
 }
 
 
 void RelocInfo::WipeOut() {
   DCHECK(IsEmbeddedObject(rmode_) || IsCodeTarget(rmode_) ||
          IsRuntimeEntry(rmode_) || IsExternalReference(rmode_) ||
          IsInternalReference(rmode_));
   if (IsInternalReference(rmode_)) {
     Memory::Address_at(pc_) = NULL;
@@ skipping 351 matching lines @@
   Address constant_pool = code ? code->constant_pool() : NULL;
   set_target_address_at(isolate, pc, constant_pool, target, icache_flush_mode);
 }
 
 EnsureSpace::EnsureSpace(Assembler* assembler) { assembler->CheckBuffer(); }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ARM_ASSEMBLER_ARM_INL_H_