Convert FrameHostMsg_DidDeleteInProcessInstance to a mojom message

FrameHostMsg_DidDeleteInProcessInstance becomes a message on
the PepperIOHost.

BUG=1157519

Change-Id: I05cd8c0faf86ddb27a9b9ac77a09239ff1e7fae8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2625999
Commit-Queue: Dave Tapuska <dtapuska@chromium.org>
Reviewed-by: Bill Budge <bbudge@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843708}

content/browser/renderer_host/pepper/pepper_renderer_connection.cc

@@ -149,8 +149,6 @@ bool PepperRendererConnection::OnMessageReceived(const IPC::Message& msg) {
   IPC_BEGIN_MESSAGE_MAP(PepperRendererConnection, msg)
     IPC_MESSAGE_HANDLER(PpapiHostMsg_CreateResourceHostsFromHost,
                         OnMsgCreateResourceHostsFromHost)
-    IPC_MESSAGE_HANDLER(FrameHostMsg_DidDeleteInProcessInstance,
-                        OnMsgDidDeleteInProcessInstance)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
 
@@ -242,8 +240,7 @@ void PepperRendererConnection::DidCreateInProcessInstance(
   in_process_host_->AddInstance(instance, instance_data);
 }
 
-void PepperRendererConnection::OnMsgDidDeleteInProcessInstance(
-    PP_Instance instance) {
+void PepperRendererConnection::DidDeleteInProcessInstance(int32_t instance) {
   // 'instance' is possibly invalid. The host must be careful not to trust it.
   in_process_host_->DeleteInstance(instance);
 }

content/browser/renderer_host/pepper/pepper_renderer_connection.h

@@ -55,13 +55,12 @@ class PepperRendererConnection
       PP_Instance instance,
       const std::vector<IPC::Message>& nested_msgs);
 
-  void OnMsgDidDeleteInProcessInstance(PP_Instance instance);
-
   // mojom::PepperPluginInstanceIOHost overrides;
   void DidCreateInProcessInstance(int32_t instance,
                                   int32_t render_frame_id,
                                   const GURL& document_url,
                                   const GURL& plugin_url) override;
+  void DidDeleteInProcessInstance(int32_t instance) override;
 
   int render_process_id_;
 

content/common/frame_messages.h

@@ -283,11 +283,6 @@ IPC_SYNC_MESSAGE_CONTROL3_3(FrameHostMsg_OpenChannelToPepperPlugin,
                             base::ProcessId /* plugin_pid */,
                             int /* plugin_child_id */)
 
-// Message from the renderer to the browser indicating the in-process instance
-// has been destroyed.
-IPC_MESSAGE_CONTROL1(FrameHostMsg_DidDeleteInProcessInstance,
-                     int32_t /* instance */)
-
 // Notification that a plugin has created a new plugin instance. The parameters
 // indicate:
 //  - The plugin process ID that we're creating the instance for.

content/common/pepper_plugin.mojom

@@ -29,6 +29,9 @@ interface PepperIOHost {
                              int32 frame_routing_id,
                              url.mojom.Url document_url,
                              url.mojom.Url plugin_url);
+
+  // Notification that an in-process instance has been destroyed.
+  DidDeleteInProcessInstance(int32 instance_id);
 };
 
 // This interface is used on the renderer IO thread and is received on the

content/renderer/pepper/pepper_browser_connection.cc

@@ -50,7 +50,8 @@ void PepperBrowserConnection::DidCreateInProcessInstance(
 }
 
 void PepperBrowserConnection::DidDeleteInProcessInstance(PP_Instance instance) {
-  Send(new FrameHostMsg_DidDeleteInProcessInstance(instance));
+  if (auto* io_host = GetIOHost())
+    io_host->DidDeleteInProcessInstance(instance);
 }
 
 void PepperBrowserConnection::SendBrowserCreate(