discardable_memory: Using mojo IPC to replace Chrome IPC

content/child/child_thread_impl.cc

Index: content/child/child_thread_impl.cc
diff --git a/content/child/child_thread_impl.cc b/content/child/child_thread_impl.cc
index 7f2755b3e00f3859bfe499adb57561c2686db6ca..afed571379594625455bc8ac55d784317518b44a 100644
--- a/content/child/child_thread_impl.cc
+++ b/content/child/child_thread_impl.cc
@@ -292,7 +292,9 @@ ChildThread* ChildThread::Get() {
 }
 
 ChildThreadImpl::Options::Options()
-    : auto_start_service_manager_connection(true), connect_to_browser(false) {}
+    : auto_start_service_manager_connection(true),
+      connect_to_browser(false),
+      init_discardable_memory(false) {}
 
 ChildThreadImpl::Options::Options(const Options& other) = default;
 
@@ -318,8 +320,14 @@ ChildThreadImpl::Options::Builder::AutoStartServiceManagerConnection(
 }
 
 ChildThreadImpl::Options::Builder&
-ChildThreadImpl::Options::Builder::ConnectToBrowser(
-  bool connect_to_browser) {
+ChildThreadImpl::Options::Builder::InitDiscardableMemory(
+    bool discardable_memory) {
+  options_.init_discardable_memory = discardable_memory;
+  return *this;
+}
+
+ChildThreadImpl::Options::Builder&
+ChildThreadImpl::Options::Builder::ConnectToBrowser(bool connect_to_browser) {
   options_.connect_to_browser = connect_to_browser;
   return *this;
 }
@@ -356,33 +364,6 @@ bool ChildThreadImpl::ChildThreadMessageRouter::RouteMessage(
   return handled;
 }
 
-class ChildThreadImpl::ClientDiscardableSharedMemoryManagerDelegate
-    : public discardable_memory::ClientDiscardableSharedMemoryManager::
-          Delegate {
- public:
-  explicit ClientDiscardableSharedMemoryManagerDelegate(
-      scoped_refptr<ThreadSafeSender> sender)
-      : sender_(sender) {}
-  ~ClientDiscardableSharedMemoryManagerDelegate() override {}
-
-  void AllocateLockedDiscardableSharedMemory(
-      size_t size,
-      discardable_memory::DiscardableSharedMemoryId id,
-      base::SharedMemoryHandle* handle) override {
-    sender_->Send(
-        new ChildProcessHostMsg_SyncAllocateLockedDiscardableSharedMemory(
-            size, id, handle));
-  }
-
-  void DeletedDiscardableSharedMemory(
-      discardable_memory::DiscardableSharedMemoryId id) override {
-    sender_->Send(new ChildProcessHostMsg_DeletedDiscardableSharedMemory(id));
-  }
-
- private:
-  scoped_refptr<ThreadSafeSender> sender_;
-};
-
 ChildThreadImpl::ChildThreadImpl()
     : route_provider_binding_(this),
       associated_interface_provider_bindings_(
@@ -406,7 +387,7 @@ ChildThreadImpl::ChildThreadImpl(const Options& options)
   Init(options);
 }
 
-scoped_refptr<base::SequencedTaskRunner> ChildThreadImpl::GetIOTaskRunner() {
+scoped_refptr<base::SingleThreadTaskRunner> ChildThreadImpl::GetIOTaskRunner() {
   if (IsInBrowserProcess())
     return browser_process_io_runner_;
   return ChildProcess::current()->io_task_runner();
@@ -594,12 +575,15 @@ void ChildThreadImpl::Init(const Options& options) {
   shared_bitmap_manager_.reset(
       new ChildSharedBitmapManager(thread_safe_sender()));
 
-  client_discardable_shared_memory_manager_delegate_ =
-      base::MakeUnique<ClientDiscardableSharedMemoryManagerDelegate>(
-          thread_safe_sender());
-  discardable_shared_memory_manager_ = base::MakeUnique<
-      discardable_memory::ClientDiscardableSharedMemoryManager>(
-      client_discardable_shared_memory_manager_delegate_.get());
+  if (options.init_discardable_memory) {
+    discardable_memory::mojom::DiscardableSharedMemoryManagerPtr manager;
+    ChildThread::Get()->GetRemoteInterfaces()->GetInterface(
+        mojo::GetProxy(&manager));
+
+    discardable_shared_memory_manager_ = base::MakeUnique<
+        discardable_memory::ClientDiscardableSharedMemoryManager>(
+        manager.PassInterface(), GetIOTaskRunner().get());
+  }
 }
 
 ChildThreadImpl::~ChildThreadImpl() {