[content] Remove Child mojom interface

This interface is no longer used.

Bug: 977637
Change-Id: I69f7fe7aac89c2da60fdb3cf8844712de90e9455
Tbr: nasko@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1707815
Commit-Queue: Ken Rockot <rockot@google.com>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#678744}

content/common/BUILD.gn

@@ -467,7 +467,6 @@ mojom("mojo_bindings") {
 
   sources = [
     "associated_interfaces.mojom",
-    "child.mojom",
     "child_process.mojom",
     "document_scoped_interface_bundle.mojom",
     "download/mhtml_file_writer.mojom",

content/common/child.mojom

-// Copyright 2017 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-module content.mojom;
-
-// This interface encapsulates a pipe between a child and browser processes
-// that each side uses to monitor the lifetime of the connection.
-interface Child {};

content/common/service_manager/child_connection.cc

@@ -12,7 +12,6 @@
 #include "base/process/process.h"
 #include "base/rand_util.h"
 #include "base/strings/string_number_conversions.h"
-#include "content/common/child.mojom.h"
 #include "content/public/common/service_manager_connection.h"
 #include "mojo/public/cpp/bindings/remote.h"
 #include "mojo/public/cpp/system/message_pipe.h"
@@ -88,7 +87,6 @@ class ChildConnection::IOThreadContext
           mojo::PendingRemote<service_manager::mojom::Service>(
               std::move(service_pipe), 0),
           std::move(metadata_receiver));
-      connector_->BindInterface(child_identity, &child_);
     }
   }
 
@@ -108,8 +106,6 @@ class ChildConnection::IOThreadContext
   // Usable from the IO thread only.
   std::unique_ptr<service_manager::Connector> connector_;
   service_manager::Identity child_identity_;
-  // ServiceManagerConnection in the child monitors the lifetime of this pipe.
-  mojom::ChildPtr child_;
   mojo::Remote<service_manager::mojom::ProcessMetadata> remote_metadata_;
   // Hold onto the process, and thus its process handle, so that the pid will
   // remain valid.

content/common/service_manager/service_manager_connection_impl.cc

@@ -19,7 +19,6 @@
 #include "base/threading/thread_checker.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "build/build_config.h"
-#include "content/common/child.mojom.h"
 #include "content/public/common/connection_filter.h"
 #include "content/public/common/service_names.mojom.h"
 #include "mojo/public/cpp/system/message_pipe.h"
@@ -49,16 +48,14 @@ ServiceManagerConnection::Factory* service_manager_connection_factory = nullptr;
 // bindings.
 class ServiceManagerConnectionImpl::IOThreadContext
     : public base::RefCountedThreadSafe<IOThreadContext>,
-      public service_manager::Service,
-      public mojom::Child {
+      public service_manager::Service {
  public:
   IOThreadContext(service_manager::mojom::ServiceRequest service_request,
                   scoped_refptr<base::SequencedTaskRunner> io_task_runner,
                   service_manager::mojom::ConnectorRequest connector_request)
       : pending_service_request_(std::move(service_request)),
         io_task_runner_(io_task_runner),
-        pending_connector_request_(std::move(connector_request)),
-        child_binding_(this) {
+        pending_connector_request_(std::move(connector_request)) {
     // This will be reattached by any of the IO thread functions on first call.
     io_thread_checker_.DetachFromThread();
   }
@@ -215,7 +212,6 @@ class ServiceManagerConnectionImpl::IOThreadContext
     ClearConnectionFiltersOnIOThread();
 
     request_handlers_.clear();
-    child_binding_.Close();
   }
 
   void ClearConnectionFiltersOnIOThread() {
@@ -248,21 +244,14 @@ class ServiceManagerConnectionImpl::IOThreadContext
                        const std::string& interface_name,
                        mojo::ScopedMessagePipeHandle interface_pipe) override {
     DCHECK(io_thread_checker_.CalledOnValidThread());
-    if ((source_info.identity.name() == mojom::kBrowserServiceName ||
-         source_info.identity.name() == mojom::kSystemServiceName) &&
-        interface_name == mojom::Child::Name_) {
-      DCHECK(!child_binding_.is_bound());
-      child_binding_.Bind(mojom::ChildRequest(std::move(interface_pipe)));
-    } else {
-      base::AutoLock lock(lock_);
-      for (auto& entry : connection_filters_) {
-        entry.second->OnBindInterface(source_info, interface_name,
-                                      &interface_pipe,
-                                      service_binding_->GetConnector());
-        // A filter may have bound the interface, claiming the pipe.
-        if (!interface_pipe.is_valid())
-          return;
-      }
+    base::AutoLock lock(lock_);
+    for (auto& entry : connection_filters_) {
+      entry.second->OnBindInterface(source_info, interface_name,
+                                    &interface_pipe,
+                                    service_binding_->GetConnector());
+      // A filter may have bound the interface, claiming the pipe.
+      if (!interface_pipe.is_valid())
+        return;
     }
   }
 
@@ -325,8 +314,6 @@ class ServiceManagerConnectionImpl::IOThreadContext
 
   std::map<std::string, ServiceRequestHandlerWithCallback> request_handlers_;
 
-  mojo::Binding<mojom::Child> child_binding_;
-
   base::WeakPtrFactory<IOThreadContext> weak_factory_{this};
 
   DISALLOW_COPY_AND_ASSIGN(IOThreadContext);