message: Fix missing namespace: int64 is in tf namespace.
  Alternative is to include tensorflow/compiler/xla/types.h but I preferred this as its more targeted in the header file.
diff: @@ -89,7 +89,8 @@ class HloFunctionImporter {
  xla::HloInstruction* instruction);
  // Converts the dimensions of an HLO instruction into an MLIR attribute.
  - mlir::ElementsAttr ConvertDimensions(llvm::ArrayRef<int64> op_dimensions);
  + mlir::ElementsAttr ConvertDimensions(
  + llvm::ArrayRef<tensorflow::int64> op_dimensions);
  // Converts Array ref to an ElementsAttr.
  mlir::ElementsAttr Convert(llvm::ArrayRef<int64_t> op_dimensions);
  