net-export NetLog dump files

Introduction

This is a WebApp that allows someone to perform post-mortem analysis of a saved Chromium NetLog dump. The full design doc can be found here.

Workflow

Generate a NetLog dump file using chrome://net-export, or download one that has been generated by someone else. NetLog dump files are platform and architecture independent.
The netlog viewer can be served locally, or accessed through a public server.

The public server is located at https://netlog-viewer.appspot.com/. (All netlog data is processed locally in your browser, not uploaded to the server.)
To serve the app locally, clone the catapult repository and serve the files from an HTTP localhost server:
```
git clone https://chromium.googlesource.com/catapult
cd catapult/netlog_viewer/netlog_viewer
ln -s ../../third_party/polymer/components/
python -m SimpleHTTPServer 8080
```
Visit http://localhost:8080/index.html in your web browser to view the netlog viewer.

Click “Choose File” which will allow you to select the file you exported earlier. From there your NetLog dump will appear as a table filled with all the dump's information. Visit the other tabs to view additional information!

Deploying

Run netlog_viewer/bin/run_dev_server_tests and verify that nothing fails.
You must be an admin on the netlog-viewer appengine project.
Authenticate with the gcloud command line tool. (Only needs to be done once.)

gcloud auth login

Build the vulcanized version that will be served by appengine.

netlog_viewer_build/build_for_appengine.py

Run app server locally, load in browser, and test that everything looks good. (Be sure to shift-reload so you aren't testing an old cached version.)

cd appengine
dev_appserver.py app.yaml

Deploy without making it the default version.

gcloud app deploy --no-promote --project netlog-viewer

Load the versioned URL that was printed and test that it works.
Send live traffic to the new version using the GCP console.

Merge history

The initial code was taken out of Chromium. The code should contain all changes made to net-internals up to chromium commit bde2d7652e5b47fc8a2c5e18e932f8ce171a9510, after which the netlog viewer code was removed from Chromium.