Cleanup: Remove extra EmbeddedWorker layering in the renderer SW code

Mechanical changes only:
- Combine ServiceWorkerScriptContext and EmbeddedWorkerContextClient,
  renaming it to ServiceWorkerContextClient
- Rename EmbeddedWorkerContextMessageFilter to ServiceWorkerContextMessageFilter

ServiceWorker/EmbeddedWorker separation in the renderer side
is currently awkwardly done and require a lot of extra methods
forwarding between the two classes, looking at the current status
probably we could combine them.

This leaves all IPC messages and browser-side code as is, at least
for now.

We could do similar cleanups for those areas too, but currently
I'm not really motivated to do further cleanups as they don't
seem causing much extra overhead in our productivity etc.
(Code-health wise we could probably do better, if anyone's
motivated to make further cleanups they're welcome)

BUG=491039
TEST=existing tests

Review URL: https://codereview.chromium.org/1136323003

Cr-Commit-Position: refs/heads/master@{#331533}

content/content_renderer.gypi

@@ -377,16 +377,14 @@
       'renderer/screen_orientation/screen_orientation_dispatcher.h',
       'renderer/screen_orientation/screen_orientation_observer.cc',
       'renderer/screen_orientation/screen_orientation_observer.h',
-      'renderer/service_worker/embedded_worker_context_client.cc',
-      'renderer/service_worker/embedded_worker_context_client.h',
-      'renderer/service_worker/embedded_worker_context_message_filter.cc',
-      'renderer/service_worker/embedded_worker_context_message_filter.h',
       'renderer/service_worker/embedded_worker_devtools_agent.cc',
       'renderer/service_worker/embedded_worker_devtools_agent.h',
       'renderer/service_worker/embedded_worker_dispatcher.cc',
       'renderer/service_worker/embedded_worker_dispatcher.h',
-      'renderer/service_worker/service_worker_script_context.cc',
-      'renderer/service_worker/service_worker_script_context.h',
+      'renderer/service_worker/service_worker_context_client.cc',
+      'renderer/service_worker/service_worker_context_client.h',
+      'renderer/service_worker/service_worker_context_message_filter.cc',
+      'renderer/service_worker/service_worker_context_message_filter.h',
       'renderer/service_worker/service_worker_type_util.cc',
       'renderer/service_worker/service_worker_type_util.h',
       'renderer/shared_memory_seqlock_reader.cc',

content/renderer/cache_storage/cache_storage_dispatcher.h

@@ -40,8 +40,6 @@ class CacheStorageDispatcher : public WorkerTaskRunner::Observer {
   void OnWorkerRunLoopStopped() override;
 
   bool Send(IPC::Message* msg);
-
-  // ServiceWorkerScriptContext calls our OnMessageReceived directly.
   bool OnMessageReceived(const IPC::Message& message);
 
   // Message handlers for CacheStorage messages from the browser process.

content/renderer/render_thread_impl.cc

@@ -107,8 +107,8 @@
 #include "content/renderer/render_view_impl.h"
 #include "content/renderer/renderer_blink_platform_impl.h"
 #include "content/renderer/scheduler/resource_dispatch_throttler.h"
-#include "content/renderer/service_worker/embedded_worker_context_message_filter.h"
 #include "content/renderer/service_worker/embedded_worker_dispatcher.h"
+#include "content/renderer/service_worker/service_worker_context_message_filter.h"
 #include "content/renderer/shared_worker/embedded_shared_worker_stub.h"
 #include "gin/public/debug.h"
 #include "gpu/GLES2/gl2extchromium.h"
@@ -563,7 +563,7 @@ void RenderThreadImpl::Init() {
 
   AddFilter((new CacheStorageMessageFilter(thread_safe_sender()))->GetFilter());
 
-  AddFilter((new EmbeddedWorkerContextMessageFilter())->GetFilter());
+  AddFilter((new ServiceWorkerContextMessageFilter())->GetFilter());
 
   GetContentClient()->renderer()->RenderThreadStarted();