Introduce AnimationWorkletProxyClient and necessary plumbing to get it in worklet messaging proxy.

third_party/WebKit/Source/modules/compositorworker/CompositorWorkerThreadTest.cpp

Index: third_party/WebKit/Source/modules/compositorworker/CompositorWorkerThreadTest.cpp
diff --git a/third_party/WebKit/Source/modules/compositorworker/CompositorWorkerThreadTest.cpp b/third_party/WebKit/Source/modules/compositorworker/CompositorWorkerThreadTest.cpp
index 848149430886f5df36b8adfa55e9b1f94daf862c..3c48e70995d97ffa40030520b3bce3ca33ca871b 100644
--- a/third_party/WebKit/Source/modules/compositorworker/CompositorWorkerThreadTest.cpp
+++ b/third_party/WebKit/Source/modules/compositorworker/CompositorWorkerThreadTest.cpp
@@ -8,7 +8,7 @@
 #include "bindings/core/v8/SourceLocation.h"
 #include "bindings/core/v8/V8GCController.h"
 #include "bindings/core/v8/WorkerOrWorkletScriptController.h"
-#include "core/dom/CompositorProxyClient.h"
+#include "core/dom/CompositorWorkerProxyClient.h"
 #include "core/inspector/ConsoleMessage.h"
 #include "core/workers/InProcessWorkerObjectProxy.h"
 #include "core/workers/ParentFrameTaskRunners.h"
@@ -60,13 +60,9 @@ class TestCompositorWorkerObjectProxy : public InProcessWorkerObjectProxy {
                                    ParentFrameTaskRunners::create(nullptr)) {}
 };
 
-class TestCompositorProxyClient
-    : public GarbageCollected<TestCompositorProxyClient>,
-      public CompositorProxyClient {
-  USING_GARBAGE_COLLECTED_MIXIN(TestCompositorProxyClient);
-
+class TestCompositorWorkerProxyClient : public CompositorWorkerProxyClient {
  public:
-  TestCompositorProxyClient() {}
+  TestCompositorWorkerProxyClient() {}
 
   void dispose() override {}
   void setGlobalScope(WorkerGlobalScope*) override {}
@@ -110,7 +106,8 @@ class CompositorWorkerThreadTest : public ::testing::Test {
     std::unique_ptr<CompositorWorkerThread> workerThread =
         CompositorWorkerThread::create(nullptr, *m_objectProxy, 0);
     WorkerClients* clients = WorkerClients::create();
-    provideCompositorProxyClientTo(clients, new TestCompositorProxyClient);
+    provideCompositorWorkerProxyClientTo(clients,
+                                         new TestCompositorWorkerProxyClient);
     workerThread->start(WorkerThreadStartupData::create(
         KURL(ParsedURLString, "http://fake.url/"), "fake user agent",
         "//fake source code", nullptr, DontPauseWorkerGlobalScopeOnStart,