Issue 23640. Implement 'analysis.getNavigation' request.

pkg/analysis_server/lib/src/protocol.dart

Index: pkg/analysis_server/lib/src/protocol.dart
diff --git a/pkg/analysis_server/lib/src/protocol.dart b/pkg/analysis_server/lib/src/protocol.dart
index 8a15ebe9e9418a6863555ef60c323afff56e7e8f..f633eb8d7460738887d4b29067ea0e32c59a9ce4 100644
--- a/pkg/analysis_server/lib/src/protocol.dart
+++ b/pkg/analysis_server/lib/src/protocol.dart
@@ -513,7 +513,7 @@ class Request {
       : _params = params != null ? params : new HashMap<String, Object>();
 
   /**
-   * Return a request parsed from the given [data], or `null` if the [data] is
+   * Return a request parsed from the given json, or `null` if the [data] is
    * not a valid json representation of a request. The [data] is expected to
    * have the following format:
    *
@@ -531,20 +531,26 @@ class Request {
    * The clientRequestTime must be an int representing the time at which
    * the client issued the request (milliseconds since epoch).
    */
-  factory Request.fromString(String data) {
-    try {
-      var result = JSON.decode(data);
-      if (result is Map) {
-        return new Request.fromJson(result);
-      }
+  factory Request.fromJson(Map<String, dynamic> result) {
+    var id = result[Request.ID];
+    var method = result[Request.METHOD];
+    if (id is! String || method is! String) {
       return null;
-    } catch (exception) {
+    }
+    var time = result[Request.CLIENT_REQUEST_TIME];
+    if (time != null && time is! int) {
+      return null;
+    }
+    var params = result[Request.PARAMS];
+    if (params is Map || params == null) {
+      return new Request(id, method, params, time);
+    } else {
       return null;
     }
   }
 
   /**
-   * Return a request parsed from the given json, or `null` if the [data] is
+   * Return a request parsed from the given [data], or `null` if the [data] is
    * not a valid json representation of a request. The [data] is expected to
    * have the following format:
    *
@@ -562,20 +568,14 @@ class Request {
    * The clientRequestTime must be an int representing the time at which
    * the client issued the request (milliseconds since epoch).
    */
-  factory Request.fromJson(Map<String, dynamic> result) {
-    var id = result[Request.ID];
-    var method = result[Request.METHOD];
-    if (id is! String || method is! String) {
-      return null;
-    }
-    var time = result[Request.CLIENT_REQUEST_TIME];
-    if (time != null && time is! int) {
+  factory Request.fromString(String data) {
+    try {
+      var result = JSON.decode(data);
+      if (result is Map) {
+        return new Request.fromJson(result);
+      }
       return null;
-    }
-    var params = result[Request.PARAMS];
-    if (params is Map || params == null) {
-      return new Request(id, method, params, time);
-    } else {
+    } catch (exception) {
       return null;
     }
   }
@@ -763,6 +763,14 @@ class Response {
               'Error during `analysis.getErrors`: invalid file.'));
 
   /**
+   * Initialize a newly created instance to represent the
+   * GET_NAVIGATION_INVALID_FILE error condition.
+   */
+  Response.getNavigationInvalidFile(Request request) : this(request.id,
+          error: new RequestError(RequestErrorCode.GET_NAVIGATION_INVALID_FILE,
+              'Error during `analysis.getNavigation`: invalid file.'));
+
+  /**
    * Initialize a newly created instance to represent an error condition caused
    * by an analysis.reanalyze [request] that specifies an analysis root that is
    * not in the current list of analysis roots.