tools/android/loading Switch the GCE worker to pull queues

tools/android/loading/gce/README.md

-# Clovis in the Cloud: Developer Guide
-
-This document describes how to collect Chromium traces using Google Compute
-Engine.
-
-[TOC]
-
-## Initial setup
-
-Install the [gcloud command line tool][1].
-
-## Deploy the code
-
-```shell
-# Build Chrome (do not use the component build).
-BUILD_DIR=out/Release
-ninja -C $BUILD_DIR -j1000 -l60 chrome chrome_sandbox
-
-# Deploy to GCE
-# CLOUD_STORAGE_PATH is the path in Google Cloud Storage under which the
-# Clovis deployment will be uploaded.
-
-./tools/android/loading/gce/deploy.sh $BUILD_DIR $CLOUD_STORAGE_PATH
-```
-
-## Start the app in the cloud
-
-Create an instance using latest ubuntu LTS:
-
-```shell
-gcloud compute instances create clovis-tracer-1 \
- --machine-type n1-standard-1 \
- --image ubuntu-14-04 \
- --zone europe-west1-c \
- --scopes cloud-platform \
- --metadata cloud-storage-path=$CLOUD_STORAGE_PATH,auto-start=true \
- --metadata-from-file \
-     startup-script=$CHROMIUM_SRC/tools/android/loading/gce/startup-script.sh
-```
-
-**Note:** To start an instance without automatically starting the app on it,
-remove the `--metadata auto-start=true` argument. This can be useful when doing
-iterative development on the instance, to be able to restart the app manually.
-
-This should output the IP address of the instance.
-Otherwise the IP address can be retrieved by doing:
-
-```shell
-gcloud compute instances list
-```
-
-**Note:** It can take a few minutes for the instance to start. You can follow
-the progress of the startup script on the gcloud console web interface (menu
-"Compute Engine" > "VM instances" then click on your instance and scroll down to
-see the "Serial console output") or from the command line using:
-
-```shell
-gcloud compute instances get-serial-port-output clovis-tracer-1
-```
-
-## Use the app
-
-Check that `http://<instance-ip>:8080/test` prints `hello` when opened in a
-browser.
-
-To send a list of URLs to process:
-
-```shell
-curl -X POST -d @urls.json http://<instance-ip>:8080/set_tasks
-```
-
-where `urls.json` is a JSON dictionary with the keys:
-
-*   `urls`: array of URLs
-*   `repeat_count`: Number of times each URL will be loaded. Each load of a URL
-    generates a separate trace file. Optional.
-*   `emulate_device`: Name of the device to emulate. Optional.
-*   `emulate_network`: Type of network emulation. Optional.
-
-You can follow the progress at `http://<instance-ip>:8080/status`.
-
-## Stop the app in the cloud
-
-```shell
-gcloud compute instances delete clovis-tracer-1
-```
-
-## Connect to the instance with SSH
-
-```shell
-gcloud compute ssh clovis-tracer-1
-```
-
-## Use the app locally
-
-From a new directory, set up a local environment:
-
-```shell
-virtualenv env
-source env/bin/activate
-pip install -r $CHROMIUM_SRC/tools/android/loading/gce/pip_requirements.txt
-```
-
-Create a JSON file describing the deployment configuration:
-
-```shell
-# CONFIG_FILE is the output json file.
-# PROJECT_NAME is the Google Cloud project.
-# CLOUD_STORAGE_PATH is the path in Google Storage where generated traces will
-# be stored.
-# CHROME_PATH is the path to the Chrome executable on the host.
-# CHROMIUM_SRC is the Chromium src directory.
-cat >$CONFIG_FILE << EOF
-{
-  "project_name" : "$PROJECT_NAME",
-  "cloud_storage_path" : "$CLOUD_STORAGE_PATH",
-  "chrome_path" : "$CHROME_PATH",
-  "src_path" : "$CHROMIUM_SRC"
-}
-EOF
-```
-
-Launch the app, passing the path to the deployment configuration file:
-
-```shell
-gunicorn --workers=1 --bind 127.0.0.1:8080 \
-    --pythonpath $CHROMIUM_SRC/tools/android/loading/gce \
-    'main:StartApp('\"$CONFIG_FILE\"')'
-```
-
-You can now [use the app][2], which is located at http://localhost:8080.
-
-Tear down the local environment:
-
-```shell
-deactivate
-```
-
-[1]: https://cloud.google.com/sdk
-[2]: #Use-the-app