Revert accidental dartium code push

content/child/simple_webmimeregistry_impl.cc

Index: content/child/simple_webmimeregistry_impl.cc
diff --git a/content/child/simple_webmimeregistry_impl.cc b/content/child/simple_webmimeregistry_impl.cc
index 205f08a7ff3e3d84453d29f0e4adbc3626b57fcc..3b3ebd62c79b3723e99614a65f05f4558369ea4c 100644
--- a/content/child/simple_webmimeregistry_impl.cc
+++ b/content/child/simple_webmimeregistry_impl.cc
@@ -40,13 +40,6 @@ WebMimeRegistry::SupportsType
       WebMimeRegistry::IsSupported : WebMimeRegistry::IsNotSupported;
 }
 
-WebMimeRegistry::SupportsType
-    SimpleWebMimeRegistryImpl::supportsDartMIMEType(
-    const WebString& mime_type) {
-  return net::IsSupportedDartMimeType(ToASCIIOrEmpty(mime_type)) ?
-      WebMimeRegistry::IsSupported : WebMimeRegistry::IsNotSupported;
-}
-
 // When debugging layout tests failures in the test shell,
 // see TestShellWebMimeRegistryImpl.
 WebMimeRegistry::SupportsType SimpleWebMimeRegistryImpl::supportsMediaMIMEType(