Add instrumentation to track down Code::CopyFrom crasher.

R=jkummerow@chromium.org
BUG=chromium:196330

Review URL: https://codereview.chromium.org/12916005

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13968 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/heap.cc

@@ -3785,7 +3785,11 @@ MaybeObject* Heap::CreateCode(const CodeDesc& desc,
   ASSERT(!isolate_->code_range()->exists() ||
       isolate_->code_range()->contains(code->address()));
   code->set_instruction_size(desc.instr_size);
+  // TODO(mstarzinger): Remove once we found the bug.
+  CHECK(reloc_info->IsByteArray());
   code->set_relocation_info(reloc_info);
+  // TODO(mstarzinger): Remove once we found the bug.
+  CHECK(code->relocation_info()->IsByteArray());
   code->set_flags(flags);
   if (code->is_call_stub() || code->is_keyed_call_stub()) {
     code->set_check_type(RECEIVER_MAP_CHECK);

src/objects.cc

@@ -8816,6 +8816,8 @@ void Code::CopyFrom(const CodeDesc& desc) {
   memmove(instruction_start(), desc.buffer, desc.instr_size);
 
   // copy reloc info
+  // TODO(mstarzinger): Remove once we found the bug.
+  CHECK(relocation_info()->IsByteArray());
   memmove(relocation_start(),
           desc.buffer + desc.buffer_size - desc.reloc_size,
           desc.reloc_size);