code: private void replaceGetCompilerOverridesCalls(
        List<TweakFunctionCall> calls) {
      for (TweakFunctionCall call : calls) {
        Node callNode = call.callNode;
        Node objNode = createCompilerDefaultValueOverridesVarNode(callNode);
        callNode.replaceWith(objNode);
        compiler.reportChangeToEnclosingScope(objNode);
      }
    }
docs: Passes the compiler default value overrides to the JS by replacing calls
  to goog.tweak.getCompilerOverrids_ with a map of tweak ID->default value;