This change satisfies https://github.com/webpack/webpack/issues/6234
which desires to change the timestamp caches from plain objects to
the ES6 Map type to avoid deopts, since v8 expects things to be
added to Maps but objects are only fast if properties aren't added
dynamically after initial assignment.
Chunks are now always in ChunkGroups
ChunkGroups have parents and children, Chunks no longer have this
AsyncDependenciesBlocks point to a ChunkGroup instead of a list of chunks
Entrypoint is now a ChunkGroup (extends from it)
move stuff graph modification methods into GraphHelpers
Change chunk id recording to source-based
Chunks have parents, siblings and children in Stats
rename AutomaticCommonsChunksPlugin to SplitChunksPlugin
add request property to origin (ChunkGroup)
remove moveToParent from AggressiveMergingPlugin
fix issues with AggressiveSplittingPlugin
remove CommonsChunkPlugin
add optimization.runtimeChunk (RuntimeChunkPlugin)
fix a filename bug for initial chunks
remove extract-text-webpack-plugin from test suite
add DebugHash to help debugging hash issues
fix issues with entry modules in different chunk as runtime
redo optimization.splitChunks options
Compilation.entrypoints is now a Map
Compilation.chunkGroups has been added
remove some unittests
update examples
update tests with CommonsChunkPlugin
exportsType falsy: It's non-harmony module
exportsType "namespace": It's a harmony module, the exports is the namespace object
exportsType "default": It's a harmony module, the exports is the default exports, named exports are properties of the default export
* Declare used properties in constructor
* Module.(re)building moved into Compilation._(re)buildingModules (Map)
* Make NormalModule.error private
* Move Module.cacheable logic into needRebuild
* More stable implemention of rebuildModule
* addModuleChain waits for Module building finished before returning
* Set built and cacheable flags correctly in Modules
* More portableId into WeakMap
* Add ModuleReason for entrypoints
* cacheable can be true/false/null in Stats
* added Stats module issuerPath
* fixes profile in stats output