Convert UtilityProcessHost to bootstrap Mojo Channel using the Shell connection

content/browser/mojo/mojo_shell_context.h

Index: content/browser/mojo/mojo_shell_context.h
diff --git a/content/browser/mojo/mojo_shell_context.h b/content/browser/mojo/mojo_shell_context.h
index 6ef9f895680f59c98b034ebcf475d5799b019313..dd15f1c471720f7de022b90ad567135976a4ef24 100644
--- a/content/browser/mojo/mojo_shell_context.h
+++ b/content/browser/mojo/mojo_shell_context.h
@@ -13,6 +13,7 @@
 #include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "content/common/content_export.h"
+#include "content/public/browser/shell_context.h"
 #include "services/shell/public/interfaces/connector.mojom.h"
 #include "services/shell/shell.h"
 
@@ -28,10 +29,11 @@ namespace content {
 
 // MojoShellContext hosts the browser's ApplicationManager, coordinating
 // app registration and interconnection.
-class CONTENT_EXPORT MojoShellContext {
+// TODO(beng): rename to ShellContextImpl.
+class CONTENT_EXPORT MojoShellContext : public ShellContext {
  public:
   MojoShellContext();
-  ~MojoShellContext();
+  ~MojoShellContext() override;
 
   // Connects an application at |name| and gets a handle to its exposed
   // services. This is only intended for use in browser code that's not part of
@@ -45,9 +47,6 @@ class CONTENT_EXPORT MojoShellContext {
       shell::mojom::InterfaceProviderPtr exposed_services,
       const shell::mojom::Connector::ConnectCallback& callback);
 
-  // Returns a shell::Connector that can be used on the IO thread.
-  static shell::Connector* GetConnectorForIOThread();
-
  private:
   class BuiltinManifestProvider;
   class Proxy;