mojo: fix little bug in DynamicServiceLoader/Runner

mojo/shell/dynamic_service_loader.cc

Index: mojo/shell/dynamic_service_loader.cc
diff --git a/mojo/shell/dynamic_service_loader.cc b/mojo/shell/dynamic_service_loader.cc
index 5939d4b12003320f69c31d35c4e80d3600e83959..a8e6914ae9e5a8bb3cd18ffa4e22dc51fd75b58d 100644
--- a/mojo/shell/dynamic_service_loader.cc
+++ b/mojo/shell/dynamic_service_loader.cc
@@ -67,8 +67,6 @@ class LocalLoader : public Loader {
     base::FilePath path;
     net::FileURLToFilePath(url, &path);
 
-    // TODO(darin): Check if the given file path exists.
-
     // Complete asynchronously for consistency with NetworkServiceLoader.
     base::MessageLoop::current()->PostTask(
         FROM_HERE,
@@ -76,7 +74,7 @@ class LocalLoader : public Loader {
                    base::Unretained(this),
                    path,
                    base::Passed(&service_handle),
-                   true));
+                   base::PathExists(path)));
   }
 };