Move message handlers that don't belong in RenderProcessHostImpl to their own files.

content/browser/renderer_host/render_process_host_impl.cc

Index: content/browser/renderer_host/render_process_host_impl.cc
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index f22ba7f05bc2469e0b834aa6857fdbd61d6d70ea..7baf0a7a57e7de3f05cc18765df158a70ea74114 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -47,7 +47,6 @@
 #include "content/browser/device_orientation/message_filter.h"
 #include "content/browser/dom_storage/dom_storage_context_impl.h"
 #include "content/browser/dom_storage/dom_storage_message_filter.h"
-#include "content/browser/download/mhtml_generation_manager.h"
 #include "content/browser/fileapi/chrome_blob_storage_context.h"
 #include "content/browser/fileapi/fileapi_message_filter.h"
 #include "content/browser/geolocation/geolocation_dispatcher_host.h"
@@ -67,6 +66,7 @@
 #include "content/browser/renderer_host/media/audio_renderer_host.h"
 #include "content/browser/renderer_host/media/media_stream_dispatcher_host.h"
 #include "content/browser/renderer_host/media/video_capture_host.h"
+#include "content/browser/renderer_host/mhtml_generation_message_filter.h"
 #include "content/browser/renderer_host/p2p/socket_dispatcher_host.h"
 #include "content/browser/renderer_host/pepper_file_message_filter.h"
 #include "content/browser/renderer_host/pepper_message_filter.h"
@@ -543,6 +543,7 @@ void RenderProcessHostImpl::CreateMessageFilters() {
   channel_->AddFilter(new content::GamepadBrowserMessageFilter(this));
   channel_->AddFilter(new content::ProfilerMessageFilter(
       content::PROCESS_TYPE_RENDERER));
+  channel_->AddFilter(new content::MHTMLGenerationMessageFilter());
 }
 
 int RenderProcessHostImpl::GetNextRoutingID() {
@@ -901,8 +902,8 @@ bool RenderProcessHostImpl::OnMessageReceived(const IPC::Message& msg) {
                           SuddenTerminationChanged)
       IPC_MESSAGE_HANDLER(ViewHostMsg_UserMetricsRecordAction,
                           OnUserMetricsRecordAction)
-      IPC_MESSAGE_HANDLER(ViewHostMsg_RevealFolderInOS, OnRevealFolderInOS)
-      IPC_MESSAGE_HANDLER(ViewHostMsg_SavedPageAsMHTML, OnSavedPageAsMHTML)
+      // Do not add more handlers here for your service! Rather, create a
+      // message filter and add it in CreateMessageFilters().

[jam, 2012/05/02 18:15:00]

I agree if there are a few messages for a feature. but if there's just one, then
I think it's fine here.

       IPC_MESSAGE_UNHANDLED_ERROR()
     IPC_END_MESSAGE_MAP_EX()
 
@@ -1342,17 +1343,6 @@ void RenderProcessHostImpl::OnUserMetricsRecordAction(
   content::RecordComputedAction(action);
 }
 
-void RenderProcessHostImpl::OnRevealFolderInOS(const FilePath& path) {
-  // Only honor the request if appropriate persmissions are granted.
-  if (ChildProcessSecurityPolicyImpl::GetInstance()->CanReadFile(GetID(),
-                                                                 path))
-    content::GetContentClient()->browser()->OpenItem(path);
-}
-
-void RenderProcessHostImpl::OnSavedPageAsMHTML(int job_id, int64 data_size) {
-  MHTMLGenerationManager::GetInstance()->MHTMLGenerated(job_id, data_size);
-}
-
 void RenderProcessHostImpl::OnCompositorSurfaceBuffersSwappedNoHost(
       int32 surface_id,
       uint64 surface_handle,