sync: Add sessions to protocol and chromiumsync python test server.

chrome/browser/sync/protocol/session_specifics.proto

Index: chrome/browser/sync/protocol/session_specifics.proto
===================================================================
--- chrome/browser/sync/protocol/session_specifics.proto	(revision 0)
+++ chrome/browser/sync/protocol/session_specifics.proto	(revision 0)
@@ -0,0 +1,91 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// Sync protocol datatype extension for sessions.
+
+syntax = "proto2";
+
+// option optimize_for = LITE_RUNTIME;
+
+package sync_pb;
+
+import "sync.proto";
+
+// Properties of session sync objects.
+message SessionSpecifics {
+  // Unique id for the session.
+  optional string session_tag = 1;
+  // Each session is composed of windows.
+  repeated SessionWindow session_window = 2;
+}
+message SessionWindow {
+  // Index of the selected tab in tabs; -1 if no tab is selected.
+  optional int32 selected_tab_index = 2 [default = -1];
+  // Type of the browser. Currently we only store browsers of type
+  // TYPE_NORMAL and TYPE_POPUP.
+  enum BrowserType {
+    TYPE_NORMAL = 1;
+    TYPE_POPUP = 2;
+  }
+  optional BrowserType browser_type = 3 [default = TYPE_NORMAL];
+  // The tabs that compose a window.
+  repeated SessionTab session_tab= 4;
+}
+message SessionTab {
+  // Visual index of the tab within its window. There may be gaps in these
+  // values.
+  optional int32 tab_visual_index = 2 [default = -1];
+  // Identifies the index of the current navigation in navigations. For
+  // example, if this is 2 it means the current navigation is navigations[2].
+  optional int32 current_navigation_index = 3 [default = -1];
+  // True if the tab is pinned.
+  optional bool pinned = 4 [default = false];
+  // If non-empty, this tab is an app tab and this is the id of the extension.
+  optional string extension_app_id = 5;
+  // Tabs are navigated, and the navigation data is here.
+  repeated TabNavigation navigation = 6;
+}
+message TabNavigation {
+  // The index in the NavigationController. If this is -1, it means this
+  // TabNavigation is bogus.
+  optional int32 index = 1 [default = -1];
+  // The virtual URL, when nonempty, will override the actual URL of the page
+  // when we display it to the user.
+  optional string virtual_url = 2;
+  // The referring URL, which can be empty.
+  optional string referrer = 3;
+  // The title of the page.
+  optional string title = 4;
+  // Content state is an opaque blob created by WebKit that represents the
+  // state of the page. This includes form entries and scroll position for each
+  // frame.
+  optional string state = 5;
+  // Types of transitions between pages.
+  enum PageTransition{
+    LINK = 0;
+    TYPED = 1;
+    AUTO_BOOKMARK = 2;
+    AUTO_SUBFRAME = 3;
+    MANUAL_SUBFRAME = 4;
+    GENERATED = 5;
+    START_PAGE = 6;
+    FORM_SUBMIT = 7;
+    RELOAD = 8;
+    KEYWORD = 9;
+    KEYWORD_GENERATED = 10;
+    CHAIN_START = 12;
+    CHAIN_END = 13;
+  }
+  // These qualifiers further define the transition.
+  enum PageTransitionQualifier {
+    CLIENT_REDIRECT = 1;
+    SERVER_REDIRECT = 2;
+  }
+  optional PageTransition page_transition = 6 [default = TYPED];
+  optional PageTransitionQualifier navigation_qualifier = 7;
+}
+
+extend EntitySpecifics {
+  optional SessionSpecifics session = 50119;
+}