More details printed for Map, DescriptorArray and TransitionArray.

tools/gdbinit

Index: tools/gdbinit
diff --git a/tools/gdbinit b/tools/gdbinit
index 20cdff618c8121ccfff9d880c97d2aa88adf106b..220959d81c2ee825a136bc0bb1ebbcc93e9e9be6 100644
--- a/tools/gdbinit
+++ b/tools/gdbinit
@@ -20,6 +20,24 @@ Print a v8 Code object from an internal code address
 Usage: jco pc
 end
 
+# Print DescriptorArray.
+define jda
+print ((v8::internal::DescriptorArray*)($arg0))->Print()
+end
+document jda
+Print a v8 DescriptorArray object
+Usage: jda tagged_ptr
+end
+
+# Print TransitionArray.
+define jta
+print ((v8::internal::TransitionArray*)($arg0))->Print()
+end
+document jta
+Print a v8 TransitionArray object
+Usage: jta tagged_ptr
+end
+
 # Print JavaScript stack trace.
 define jst
 print v8::internal::Isolate::Current()->PrintStack(stdout)