Replace net-internals/export tab with deprecation msg and button to show old UI.

chrome/browser/resources/net_internals/export_view.html

Index: chrome/browser/resources/net_internals/export_view.html
diff --git a/chrome/browser/resources/net_internals/export_view.html b/chrome/browser/resources/net_internals/export_view.html
index 92dc0818a9bc46bedc175102afc7db6ddd8e2237..8f44e563459f943601875ef3442be0f56748209e 100644
--- a/chrome/browser/resources/net_internals/export_view.html
+++ b/chrome/browser/resources/net_internals/export_view.html
@@ -18,7 +18,24 @@
 </style>
 
 <div id=export-view-tab-content class=content-box>
-  <div>
+  <div id=export-view-deprecated-notice>
+    <b>NOTICE</b>: chrome://net-internals is being deprecated.

[eroman, 2017/02/28 00:24:40]

How about simplifying the text to just talk about net-export:
-----------------------------
WARNING: chrome://net-net internals is being deprecated for exporting log files
(crbug.com/678386)

Use chrome://net-export instead.

<button>Show the deprecated UI</button>
-----------------------------

My main points are:
  (1) Include the bug number, so people have somewhere to complain / find more
information
  (2) Let's not confuse things with net-internals viewing deprecation yet (don't
want to indicate it as such until the replacement has tests and is updated)

[wangyix1, 2017/02/28 01:49:14]

Done.

+    <p>
+      To generate net logs, please use
+      <a href="chrome://net-export" target="_self">chrome://net-export</a>.
+    </p>
+    <p>
+      To import and view net logs, please use
+      <a href="https://github.com/catapult-project/catapult/tree/master/netlog_viewer" target="_blank">Catapult netlog-viewer</a>.
+    </p>
+    <p>
+      To continue using the deprecated export tab anyway, click the button below.
+    </p>
+    <button id=export-view-show-deprecated-ui>Show export UI</button>
+  
+  </div>
+
+  <div style="display: none" id=export-view-ui-deprecated>
     <input id=export-view-privacy-stripping-checkbox type=checkbox checked=yes>
     <label for=export-view-privacy-stripping-checkbox>
       Strip private information (cookies and credentials).
@@ -40,7 +57,7 @@
         How to provide data for bug reports
       </a>
     </div>
-
+  
   </div>
 
   <a style="display: none" id=export-view-download-anchor download="net-internals-log.json"></a>