Add a timeline view to about:net-internals.

chrome/browser/resources/net_internals/top_mid_bottom_view.js

Index: chrome/browser/resources/net_internals/top_mid_bottom_view.js
===================================================================
--- chrome/browser/resources/net_internals/top_mid_bottom_view.js	(revision 109671)
+++ chrome/browser/resources/net_internals/top_mid_bottom_view.js	(working copy)
@@ -10,7 +10,8 @@
 
   /**
    * This view stacks three boxes -- one at the top, one at the bottom, and
-   * one that fills the remaining space between those two.
+   * one that fills the remaining space between those two.  Either the top
+   * or the bottom bar may be null.
    *
    *  +----------------------+
    *  |      topbar          |
@@ -47,23 +48,33 @@
       superClass.prototype.setGeometry.call(this, left, top, width, height);
 
       // Calculate the vertical split points.
-      var topbarHeight = this.topView_.getHeight();
-      var bottombarHeight = this.bottomView_.getHeight();
+      var topbarHeight = 0;

[eroman, 2011/11/16 04:03:46]

so the idea here is to make the subviews optional?

[mmenke, 2011/11/16 18:39:35]

Yea.  I'm actually thinking we may want to allow multiple subviews at both the
top and bottom, which will allow use to have some sort of details pane at the
bottom.  Could also make a horizontal splitter view instead.

+      if (this.topView_)
+        topbarHeight = this.topView_.getHeight();
+      var bottombarHeight = 0;
+      if (this.bottomView_)
+        bottombarHeight = this.bottomView_.getHeight();
       var middleboxHeight = height - (topbarHeight + bottombarHeight);
+      if (middleboxHeight < 0) middleboxHeight = 0;
 
       // Position the boxes using calculated split points.
-      this.topView_.setGeometry(left, top, width, topbarHeight);
-      this.midView_.setGeometry(left, this.topView_.getBottom(),
-                                width, middleboxHeight);
-      this.bottomView_.setGeometry(left, this.midView_.getBottom(),
-                                   width, bottombarHeight);
+      if (this.topView_)
+        this.topView_.setGeometry(left, top, width, topbarHeight);
+      this.midView_.setGeometry(left, top + topbarHeight, width,
+                                middleboxHeight);
+      if (this.bottomView_) {
+        this.bottomView_.setGeometry(left, top + topbarHeight + middleboxHeight,
+                                     width, bottombarHeight);
+      }
     },
 
     show: function(isVisible) {
       superClass.prototype.show.call(this, isVisible);
-      this.topView_.show(isVisible);
+      if (this.topView_)
+        this.topView_.show(isVisible);
       this.midView_.show(isVisible);
-      this.bottomView_.show(isVisible);
+      if (this.bottomView_)
+        this.bottomView_.show(isVisible);
     }
   };