Trusted plugin: Remove EnumerateManifestKeys.

ppapi/native_client/src/trusted/plugin/manifest.h

Index: ppapi/native_client/src/trusted/plugin/manifest.h
diff --git a/ppapi/native_client/src/trusted/plugin/manifest.h b/ppapi/native_client/src/trusted/plugin/manifest.h
index aa1ad3bce6ecc6ed8dda849ca4d408336e7c273e..03ed71ee945e01de7e941a478e95f0cffb38ff97 100644
--- a/ppapi/native_client/src/trusted/plugin/manifest.h
+++ b/ppapi/native_client/src/trusted/plugin/manifest.h
@@ -47,12 +47,6 @@ class Manifest {
                              bool* uses_nonsfi_mode,
                              ErrorInfo* error_info) const = 0;
 
-  // Gets the file names from the "files" section of the manifest.  No
-  // checking that the keys' values are proper ISA dictionaries -- it
-  // is assumed that other consistency checks take care of that, and
-  // that the keys are appropriate for use with ResolveKey.
-  virtual bool GetFileKeys(std::set<nacl::string>* keys) const = 0;
-
   // Resolves a key from the "files" section to a fully resolved URL,
   // i.e., relative URL values are fully expanded relative to the
   // manifest's URL.  Fills in |pnacl_options| if