Stub in more IPC attachment brokering functionality.

ipc/ipc_message_attachment_set.cc

Index: ipc/ipc_message_attachment_set.cc
diff --git a/ipc/ipc_message_attachment_set.cc b/ipc/ipc_message_attachment_set.cc
index cb74a5aaf07193c8d57367923a52557d40999ab4..67e24678c3db3858589a7caaf5d5ae65abe2b358 100644
--- a/ipc/ipc_message_attachment_set.cc
+++ b/ipc/ipc_message_attachment_set.cc
@@ -7,6 +7,7 @@
 #include <algorithm>
 #include "base/logging.h"
 #include "base/posix/eintr_wrapper.h"
+#include "ipc/brokerable_attachment.h"
 #include "ipc/ipc_message_attachment.h"
 
 #if defined(OS_POSIX)
@@ -52,6 +53,14 @@ unsigned MessageAttachmentSet::num_mojo_handles() const {
   });
 }
 
+unsigned MessageAttachmentSet::num_brokerable_attachments() const {
+  return std::count_if(attachments_.begin(), attachments_.end(),

[Tom Sepez, 2015/06/19 18:04:11]

C++11 std library not yet allowed AFAIK (as much as I like these constructs). I
also worry about incrementing/decrementing the refcount
on each call.

[erikchen, 2015/06/23 22:37:00]

The latter problem could be fixed, but the former cannot. I was copying the code
from the two previous methods. I've created a new function in this translation
unit that does the counting, and I've changed all three methods to use this new
function.

+                       [](scoped_refptr<MessageAttachment> i) {
+                         return i->GetType() ==
+                                MessageAttachment::TYPE_BROKERABLE_ATTACHMENT;
+                       });
+}
+
 unsigned MessageAttachmentSet::size() const {
   return static_cast<unsigned>(attachments_.size());
 }
@@ -114,6 +123,20 @@ void MessageAttachmentSet::CommitAll() {
   consumed_descriptor_highwater_ = 0;
 }
 
+std::vector<scoped_refptr<BrokerableAttachment>>
+MessageAttachmentSet::PeekBrokerableAttachments() const {
+  std::vector<scoped_refptr<BrokerableAttachment>> output;
+  for (const scoped_refptr<MessageAttachment>& attachment : attachments_) {
+    if (attachment->GetType() ==
+        MessageAttachment::TYPE_BROKERABLE_ATTACHMENT) {
+      scoped_refptr<BrokerableAttachment> brokerable_attachment(
+          static_cast<BrokerableAttachment*>(attachment.get()));
+      output.push_back(brokerable_attachment);
+    }
+  }
+  return output;
+}
+
 #if defined(OS_POSIX)
 
 void MessageAttachmentSet::PeekDescriptors(base::PlatformFile* buffer) const {