[OLD ATTEMPT, DO NOT REVIEW] mustash: Enable connections to mus from the Chrome renderer

content/browser/mojo/mojo_shell_client_host.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "base/thread_task_runner_handle.h"
 #include "content/browser/mojo/mojo_shell_client_host.h"
 #include "content/common/mojo/mojo_messages.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/common/mojo_shell_connection.h"
 #include "ipc/ipc_sender.h"
+#include "mojo/application/public/cpp/application_connection.h"
 #include "mojo/application/public/cpp/application_impl.h"
 #include "mojo/converters/network/network_type_converters.h"
 #include "mojo/shell/application_manager.mojom.h"
 #include "third_party/mojo/src/mojo/edk/embedder/embedder.h"
 #include "third_party/mojo/src/mojo/edk/embedder/platform_channel_pair.h"
 #include "third_party/mojo/src/mojo/edk/embedder/scoped_platform_handle.h"
 
 namespace content {
 namespace {
 
@@ skipping 74 matching lines @@
   SetMojoApplicationInstanceURL(render_process_host, url);
 }
 
 std::string GetMojoApplicationInstanceURL(
     RenderProcessHost* render_process_host) {
   InstanceURL* instance_url = static_cast<InstanceURL*>(
       render_process_host->GetUserData(kMojoShellInstanceURL));
   return instance_url ? instance_url->get() : std::string();
 }
 
+int GetRenderProcessIDFromConnection(mojo::ApplicationConnection* connection) {
+  // Just use the host name for finding the string to avoid checking for
+  // slashes.
+  const char kChromeRenderer[] = "chrome_renderer";
+  const std::string& url = connection->GetRemoteApplicationURL();
+  size_t pos = url.find_last_of(kChromeRenderer);
+  std::string val(url.substr(pos + 1, url.size() - pos - 2));
+  int render_process_id = 0;
+  if (!base::StringToInt(val, &render_process_id))
+    return 0;
+  return render_process_id;
+}
+
 }  // namespace content