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Related to NativeScript/android#1263

What is the current behavior?

The parameters passed to the mksnapshot tool are hardcoded in the webpack plugin (for example the --profile_deserialization flag).

What is the new behavior?

The parameters passed to the mksnapshot tool are retrieved from the settings.json file of the installed android runtime. A fallback mechanism is provided for older android runtimes which do not have those parameters.

Why is this change required?

Recent V8 versions (notably >= 7.0) have become very strict on the parameters passed to mksnapshot. They must exactly match the parameters used to create V8's internal snapshot during the compilation process. Otherwise the layout of the snapshot binary might become invalid and result into segmentation faults. Because those parameters are very strictly related to the V8 version it makes more sense to store them as part of the runtime as they might change often.

For reference, here's a related issue in which we have discussed with Google engineers, various crashes related to those parameters: https://bugs.chromium.org/p/v8/issues/detail?id=8576. For example the --turbo_instruction_scheduling flag must now be specified.