Reland Implement .eh_frame writer and disassembler.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index b64ae2c1e7b30d506db1a691eb13d56a2553d6a1..d374bdad2603c43fec0014d68a72e55b35506568 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -61,6 +61,7 @@
 #ifdef ENABLE_DISASSEMBLER
 #include "src/disasm.h"
 #include "src/disassembler.h"
+#include "src/eh-frame.h"
 #endif
 
 namespace v8 {
@@ -14349,6 +14350,14 @@ void Code::Disassemble(const char* name, std::ostream& os) {  // NOLINT
     it.rinfo()->Print(GetIsolate(), os);
   }
   os << "\n";
+
+  if (has_unwinding_info()) {
+    os << "UnwindingInfo (size = " << unwinding_info_size() << ")\n";
+    EhFrameDisassembler eh_frame_disassembler(unwinding_info_start(),
+                                              unwinding_info_end());
+    eh_frame_disassembler.DisassembleToStream(os);
+    os << "\n";
+  }
 }
 #endif  // ENABLE_DISASSEMBLER