[worklets] Split up InProcessWorkerMessagingProxy into a base+worker class.

third_party/WebKit/Source/core/core.gypi

 {
     'includes': [
         'core_generated.gypi',
     ],
     'variables': {
         # Files for which bindings (.cpp and .h files) will be generated
         'core_idl_files': [
             'animation/KeyframeEffect.idl',
             'animation/AnimationEffectReadOnly.idl',
             'animation/AnimationEffectTiming.idl',
@@ skipping 2286 matching lines @@
             'workers/DedicatedWorkerGlobalScope.cpp',
             'workers/DedicatedWorkerGlobalScope.h',
             'workers/DedicatedWorkerGlobalScopeProxyProvider.cpp',
             'workers/DedicatedWorkerGlobalScopeProxyProvider.h',
             'workers/DedicatedWorkerMessagingProxy.cpp',
             'workers/DedicatedWorkerMessagingProxy.h',
             'workers/DedicatedWorkerThread.cpp',
             'workers/DedicatedWorkerThread.h',
             'workers/InProcessWorkerBase.cpp',
             'workers/InProcessWorkerBase.h',
-            'workers/InProcessWorkerGlobalScopeProxy.h',
             'workers/InProcessWorkerMessagingProxy.cpp',
             'workers/InProcessWorkerMessagingProxy.h',
             'workers/InProcessWorkerObjectProxy.cpp',
             'workers/InProcessWorkerObjectProxy.h',
             'workers/MainThreadWorkletGlobalScope.cpp',
             'workers/MainThreadWorkletGlobalScope.h',
             'workers/ParentFrameTaskRunners.cpp',
             'workers/ParentFrameTaskRunners.h',
             'workers/SharedWorker.cpp',
             'workers/SharedWorker.h',
             'workers/SharedWorkerGlobalScope.cpp',
             'workers/SharedWorkerGlobalScope.h',
             'workers/SharedWorkerRepositoryClient.h',
             'workers/SharedWorkerThread.cpp',
             'workers/SharedWorkerThread.h',
+            'workers/ThreadedGlobalScopeProxy.h',
+            'workers/ThreadedMessagingProxyBase.cpp',
+            'workers/ThreadedMessagingProxyBase.h',
             'workers/ThreadedWorkletGlobalScope.cpp',
             'workers/ThreadedWorkletGlobalScope.h',
             'workers/ThreadedWorkletGlobalScopeProxy.h',
             'workers/Worker.cpp',
             'workers/Worker.h',
             'workers/WorkerBackingThread.cpp',
             'workers/WorkerBackingThread.h',
             'workers/WorkerClients.cpp',
             'workers/WorkerClients.h',
             'workers/WorkerEventQueue.cpp',
@@ skipping 1201 matching lines @@
             'testing/TypeConversions.h',
             'testing/UnionTypesTest.cpp',
             'testing/UnionTypesTest.h',
             'testing/v8/WebCoreTestSupport.cpp',
             'testing/v8/WebCoreTestSupport.h',
             'testing/WorkerInternals.cpp',
             'testing/WorkerInternals.h',
         ],
     }
 }