Introduce base classes for blame contexts

tracing/tracing/extras/chrome/blame_context/frame_tree_node.html

Index: tracing/tracing/extras/chrome/blame_context/frame_tree_node.html
diff --git a/tracing/tracing/extras/chrome/frame_tree_node.html b/tracing/tracing/extras/chrome/blame_context/frame_tree_node.html
similarity index 45%
rename from tracing/tracing/extras/chrome/frame_tree_node.html
rename to tracing/tracing/extras/chrome/blame_context/frame_tree_node.html
index dde8fc28d1f8bc6a061fa07169cf7f27660fe872..6ba658ae52e44cb2dc04f05ca20a9cbfdd480114 100644
--- a/tracing/tracing/extras/chrome/frame_tree_node.html
+++ b/tracing/tracing/extras/chrome/blame_context/frame_tree_node.html
@@ -5,28 +5,34 @@ Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file.
 -->
 
-<link rel="import" href="/tracing/model/object_instance.html">
+<link rel="import" href="/tracing/extras/chrome/blame_context/frame_blame_context_base.html">
 
 <script>
 'use strict';
 
+/**
+ * @fileoverview Trace viewer side's correspondence of Chrome's
+ * content::FrameTreeNode class.
+ *
+ */
 tr.exportTo('tr.e.chrome', function() {
-  var constants = tr.e.cc.constants;
-
-  var ObjectSnapshot = tr.model.ObjectSnapshot;
-  var ObjectInstance = tr.model.ObjectInstance;
+  var FrameBlameContextBaseSnapshot = tr.e.chrome.FrameBlameContextBaseSnapshot;
+  var FrameBlameContextBaseInstance = tr.e.chrome.FrameBlameContextBaseInstance;
 
   function FrameTreeNodeSnapshot() {
-    ObjectSnapshot.apply(this, arguments);
+    FrameBlameContextBaseSnapshot.apply(this, arguments);
   }
 
   FrameTreeNodeSnapshot.prototype = {
-    __proto__: ObjectSnapshot.prototype,
+    __proto__: FrameBlameContextBaseSnapshot.prototype,
 
-    preInitialize: function() {
+    get crossProcessCounterpart() {
+      if (this.args.RenderFrame instanceof tr.e.chrome.RenderFrameSnapshot)
+        return this.args.RenderFrame;

[Sami, 2016/05/27 14:03:09]

s/.RenderFrame/.renderFrame/?

[Xiaocheng, 2016/05/30 07:55:55]

Nope. The field name "RenderFrame" is set in Chrome.

Or maybe we should change both of them.

[Sami, 2016/05/31 16:59:36]

Oh really? Could you point me to where it's coming from? I couldn't spot it with
a quick code search.

[benjhayden, 2016/05/31 17:37:12]

https://code.google.com/p/chromium/codesearch#chromium/src/content/browser/fr...

[Sami, 2016/05/31 18:15:10]

Ah I see, thanks. Yeah, that should probably be called "frame_frame" instead.

[benjhayden, 2016/05/31 19:49:59]

If you meant "render_frame", then I agree.

[Xiaocheng, 2016/06/01 01:22:11]

The naming is kind of inconsistent. I'll fix it in a separate patch.

     },
 
-    initialize: function() {
+    get url() {
+      return this.args.url;
     },
 
     get userFriendlyName() {
@@ -34,19 +40,23 @@ tr.exportTo('tr.e.chrome', function() {
     }
   };
 
-  ObjectSnapshot.register(
+  tr.model.ObjectSnapshot.register(
       FrameTreeNodeSnapshot,
       {typeName: 'FrameTreeNode'});
 
   function FrameTreeNodeInstance() {
-    ObjectInstance.apply(this, arguments);
+    FrameBlameContextBaseInstance.apply(this, arguments);
   }
 
   FrameTreeNodeInstance.prototype = {
-    __proto__: ObjectInstance.prototype
+    __proto__: FrameBlameContextBaseInstance.prototype,
+
+    get isTracedByRenderer() {
+      return false;
+    }
   };
 
-  ObjectInstance.register(
+  tr.model.ObjectInstance.register(
       FrameTreeNodeInstance,
       {typeName: 'FrameTreeNode'});