Auto merge of #22210 - asajeffrey:magicleap-very-well-hidden-flag, r=jdm

Add debuggable flag to magicleap taildata

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python/servo/package_commands.py

@@ -246,6 +246,9 @@ class PackageCommands(CommandBase):
                 mabu,
                 "-o", target_dir,
                 "-t", build_type,
+                # Servo SEGVs if we don't set the debuggable flag in the mpk's taildata
+                # https://github.com/servo/servo/issues/22188
+                "--add-tail-data-args=--debuggable",
                 package
             ]
             try: