Fix error handling in analysis.getError.

editor/tools/plugins/com.google.dart.server/src/com/google/dart/server/AnalysisServer.java

 /*
  * Copyright (c) 2014, the Dart project authors.
  *
  * Licensed under the Eclipse Public License v1.0 (the "License"); you may not use this file except
  * in compliance with the License. You may obtain a copy of the License at
  *
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Unless required by applicable law or agreed to in writing, software distributed under the License
  * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
@@ skipping 33 matching lines @@
    * been computed, or the most recently computed errors for the given file are out of date, then the
    * response for this request will be delayed until they have been computed. If some or all of the
    * errors for the file cannot be computed, then the subset of the errors that can be computed will
    * be returned and the response will contain an error to indicate why the errors could not be
    * computed.
    *
    * This request is intended to be used by clients that cannot asynchronously apply updated error
    * information. Clients that can apply error information as it becomes available should use the
    * information provided by the 'analysis.errors' notification.
    *
+   * If a request is made for a file which does not exist, or which is not currently subject to
+   * analysis (e.g. because it is not associated with any analysis root specified to
+   * analysis.setAnalysisRoots), an error of type GET_ERRORS_INVALID_FILE will be generated.
+   *
    * @param file The file for which errors are being requested.
    */
   public void analysis_getErrors(String file, GetErrorsConsumer consumer);
 
   /**
    * {@code analysis.getHover}
    *
    * Return the hover information associate with the given location. If some or all of the hover
    * information is not available at the time this request is processed the information will be
    * omitted from the response.
@@ skipping 331 matching lines @@
 
   /**
    * Start the analysis server.
    *
    * @param millisToRestart the number of milliseconds to wait for an unresponsive server before
    *          restarting it, or zero if the server should not be restarted.
    */
   public void start(long millisToRestart) throws Exception;
 
 }