ipc: Move //crypto dependency into a Windows-only file.

ipc/ipc_channel_reader_unittest.cc

Index: ipc/ipc_channel_reader_unittest.cc
diff --git a/ipc/ipc_channel_reader_unittest.cc b/ipc/ipc_channel_reader_unittest.cc
index 2ecc98b1874ba376e0f034a91eea208cfb07cbbc..cbcd5dc5189cafa9a2410922e9b1216e72ada5bd 100644
--- a/ipc/ipc_channel_reader_unittest.cc
+++ b/ipc/ipc_channel_reader_unittest.cc
@@ -6,7 +6,6 @@
 
 #include <set>
 
-#include "crypto/random.h"
 #include "ipc/attachment_broker.h"
 #include "ipc/brokerable_attachment.h"
 #include "ipc/ipc_channel_reader.h"
@@ -18,17 +17,9 @@ namespace internal {
 
 namespace {
 
-BrokerableAttachment::AttachmentId GenerateAttachementId() {
-  BrokerableAttachment::AttachmentId result;
-  crypto::RandBytes(result.nonce, BrokerableAttachment::kNonceSize);
-  return result;
-}
-
 class MockAttachment : public BrokerableAttachment {
  public:
-  MockAttachment(int internal_state)
-      : BrokerableAttachment(GenerateAttachementId(), true),
-        internal_state_(internal_state) {}
+  MockAttachment(int internal_state) : internal_state_(internal_state) {}
   MockAttachment(BrokerableAttachment::AttachmentId id)
       : BrokerableAttachment(id, true), internal_state_(-1) {}