Make IPC::Channel polymorphic

This change makes each platform specific ChannelImpl into
a subclass of Channel: ChannelPosix, ChannelWin, ChannelNacl.
delegated functions are now virtual.

TEST=none
BUG=377980
R=darin@chromium.org, jam@chromium.org

Review URL: https://codereview.chromium.org/310293002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@275505 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: 2f60c9b74db6c61424a5a9c731acef26a9260c9c
diff --git a/ipc/ipc_sync_channel_unittest.cc b/ipc/ipc_sync_channel_unittest.cc
index 817f17e..a145f6b 100644
--- a/ipc/ipc_sync_channel_unittest.cc
+++ b/ipc/ipc_sync_channel_unittest.cc
@@ -1722,7 +1722,7 @@
     VLOG(1) << __FUNCTION__ << " Sending reply: " << reply_text_;
     SyncChannelNestedTestMsg_String::WriteReplyParams(reply_msg, reply_text_);
     Send(reply_msg);
-    ASSERT_EQ(channel()->peer_pid(), base::GetCurrentProcId());
+    ASSERT_EQ(channel()->GetPeerPID(), base::GetCurrentProcId());
     Done();
   }
 
@@ -1751,7 +1751,7 @@
     (void)expected_text_;
 
     VLOG(1) << __FUNCTION__ << " Received reply: " << response;
-    ASSERT_EQ(channel()->peer_pid(), base::GetCurrentProcId());
+    ASSERT_EQ(channel()->GetPeerPID(), base::GetCurrentProcId());
     Done();
   }