Revert of Remove IPC::BrokerableAttachment.

ipc/ipc_channel_mojo.cc

Index: ipc/ipc_channel_mojo.cc
diff --git a/ipc/ipc_channel_mojo.cc b/ipc/ipc_channel_mojo.cc
index 5d468ab59b5446ef8cac9482bad6a8a375c95952..e71baff895e6892d9dc36d6d0bfc44f1f159b7eb 100644
--- a/ipc/ipc_channel_mojo.cc
+++ b/ipc/ipc_channel_mojo.cc
@@ -126,14 +126,14 @@
 
 MojoResult WrapAttachmentImpl(MessageAttachment* attachment,
                               mojom::SerializedHandlePtr* serialized) {
-  if (attachment->GetType() == MessageAttachment::Type::MOJO_HANDLE) {
+  if (attachment->GetType() == MessageAttachment::TYPE_MOJO_HANDLE) {
     *serialized = CreateSerializedHandle(
         static_cast<internal::MojoHandleAttachment&>(*attachment).TakeHandle(),
         mojom::SerializedHandle::Type::MOJO_HANDLE);
     return MOJO_RESULT_OK;
   }
 #if defined(OS_POSIX)
-  if (attachment->GetType() == MessageAttachment::Type::PLATFORM_FILE) {
+  if (attachment->GetType() == MessageAttachment::TYPE_PLATFORM_FILE) {
     // We dup() the handles in IPC::Message to transmit.
     // IPC::MessageAttachmentSet has intricate lifecycle semantics
     // of FDs, so just to dup()-and-own them is the safest option.
@@ -150,7 +150,10 @@
   }
 #endif
 #if defined(OS_MACOSX)
-  DCHECK_EQ(attachment->GetType(), MessageAttachment::Type::MACH_PORT);
+  DCHECK_EQ(attachment->GetType(),
+            MessageAttachment::TYPE_BROKERABLE_ATTACHMENT);
+  DCHECK_EQ(static_cast<BrokerableAttachment&>(*attachment).GetBrokerableType(),
+            BrokerableAttachment::MACH_PORT);
   internal::MachPortAttachmentMac& mach_port_attachment =
       static_cast<internal::MachPortAttachmentMac&>(*attachment);
   MojoResult result = WrapMachPort(mach_port_attachment.get_mach_port(),
@@ -158,7 +161,10 @@
   mach_port_attachment.reset_mach_port_ownership();
   return result;
 #elif defined(OS_WIN)
-  DCHECK_EQ(attachment->GetType(), MessageAttachment::Type::WIN_HANDLE);
+  DCHECK_EQ(attachment->GetType(),
+            MessageAttachment::TYPE_BROKERABLE_ATTACHMENT);
+  DCHECK_EQ(static_cast<BrokerableAttachment&>(*attachment).GetBrokerableType(),
+            BrokerableAttachment::WIN_HANDLE);
   internal::HandleAttachmentWin& handle_attachment =
       static_cast<internal::HandleAttachmentWin&>(*attachment);
   MojoResult result = WrapPlatformHandle(
@@ -405,9 +411,18 @@
   std::vector<mojom::SerializedHandlePtr> output_handles;
   MessageAttachmentSet* set = message->attachment_set();
 
-  for (unsigned i = 0; result == MOJO_RESULT_OK && i < set->size(); ++i) {
-    result = WrapAttachment(set->GetAttachmentAt(i).get(), &output_handles);
-  }
+  for (unsigned i = 0;
+       result == MOJO_RESULT_OK && i < set->num_non_brokerable_attachments();
+       ++i) {
+    result = WrapAttachment(set->GetNonBrokerableAttachmentAt(i).get(),
+                            &output_handles);
+  }
+  for (unsigned i = 0;
+       result == MOJO_RESULT_OK && i < set->num_brokerable_attachments(); ++i) {
+    result = WrapAttachment(set->GetBrokerableAttachmentAt(i).get(),
+                            &output_handles);
+  }
+
   set->CommitAllDescriptors();
 
   if (!output_handles.empty())