message: Add LOCKS_EXCLUDED to a few FunctionLibraryDefinition methods
diff: @@ -363,19 +363,20 @@ class FunctionLibraryDefinition : public OpRegistryInterface {
  // a non-OK status if "func" was not found in the library, OK otherwise.
  // Please be careful when replacing function: make sure all previous pointers
  // returned by `Find()` are no longer in use.
  - Status ReplaceFunction(const string& func, const FunctionDef& fdef);
  + Status ReplaceFunction(const string& func, const FunctionDef& fdef)
  + LOCKS_EXCLUDED(mu_);
  // Replaces the gradient corresponding to `grad.function_name()`. Returns
  // a non-OK status if "grad.function_name()" was not found in the library, OK
  // otherwise.
  - Status ReplaceGradient(const GradientDef& grad);
  + Status ReplaceGradient(const GradientDef& grad) LOCKS_EXCLUDED(mu_);
  // Removes the function corresponding to 'func'. Returns a non-OK status if
  // 'func' was not found in the library, OK otherwise.
  // Please be careful when removing function: make sure there are no other
  // nodes using the function, and all previous pointers returned by `Find()`
  // are no longer in use.
  - Status RemoveFunction(const string& func);
  + Status RemoveFunction(const string& func) LOCKS_EXCLUDED(mu_);
  // Adds the functions and gradients in 'other' to this function library.
  // Duplicate functions and gradients are ignored.
  