Bootstrap Mojo IPC independent of Chrome IPC

content/zygote/zygote_linux.cc

Index: content/zygote/zygote_linux.cc
diff --git a/content/zygote/zygote_linux.cc b/content/zygote/zygote_linux.cc
index cab47220876e206e41125985aec45effb007d10d..89fe021ac3bbadd3eed4defe52480911ce1ef6b4 100644
--- a/content/zygote/zygote_linux.cc
+++ b/content/zygote/zygote_linux.cc
@@ -436,9 +436,15 @@ int Zygote::ForkWithRealPid(const std::string& process_type,
       DLOG(ERROR) << "Failed to find kPrimaryIPCChannel in FD mapping";
       return -1;
     }
+    int mojo_channel_fd = LookUpFd(fd_mapping, kMojoIPCChannel);
+    if (mojo_channel_fd < 0) {
+      DLOG(ERROR) << "Failed to find kMojoIPCChannel in FD mapping";
+      return -1;
+    }
     std::vector<int> fds;
     fds.push_back(ipc_channel_fd);  // kBrowserFDIndex
     fds.push_back(pid_oracle.get());  // kPIDOracleFDIndex
+    fds.push_back(mojo_channel_fd);  // kMojoParentFDIndex
     pid = helper->Fork(process_type, fds, channel_id);
 
     // Helpers should never return in the child process.