Refactor GuestViewContainer to split out WebView related logic and MimeHandlerView related logic.

extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc

Index: extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc
diff --git a/extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc b/extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc
index 356fac39cdce57219c0436abe068f1f818532c91..69f70e84fe35a09534a279063771d5a0e934e2f6 100644
--- a/extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc
+++ b/extensions/renderer/guest_view/guest_view_internal_custom_bindings.cc
@@ -11,7 +11,7 @@
 #include "content/public/renderer/v8_value_converter.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_messages.h"
-#include "extensions/renderer/guest_view/guest_view_container.h"
+#include "extensions/renderer/guest_view/extensions_guest_view_container.h"
 #include "extensions/renderer/script_context.h"
 #include "v8/include/v8.h"
 
@@ -41,11 +41,11 @@ void GuestViewInternalCustomBindings::AttachGuest(
   CHECK(args.Length() < 4 || args[3]->IsFunction());
 
   int element_instance_id = args[0]->Int32Value();
-  // An element instance ID uniquely identifies a GuestViewContainer within
-  // a RenderView.
-  GuestViewContainer* guest_view_container =
-      GuestViewContainer::FromID(context()->GetRenderView()->GetRoutingID(),
-                                 element_instance_id);
+  // An element instance ID uniquely identifies a ExtensionsGuestViewContainer
+  // within a RenderView.
+  ExtensionsGuestViewContainer* guest_view_container =
+      ExtensionsGuestViewContainer::FromID(
+          context()->GetRenderView()->GetRoutingID(), element_instance_id);
 
   // TODO(fsamuel): Should we be reporting an error if the element instance ID
   // is invalid?
@@ -64,8 +64,8 @@ void GuestViewInternalCustomBindings::AttachGuest(
         static_cast<base::DictionaryValue*>(params_as_value.release()));
   }
 
-  linked_ptr<GuestViewContainer::AttachRequest> request(
-      new GuestViewContainer::AttachRequest(
+  linked_ptr<ExtensionsGuestViewContainer::AttachRequest> request(
+      new ExtensionsGuestViewContainer::AttachRequest(
           element_instance_id,
           guest_instance_id,
           params.Pass(),