Similar to script execution, this spins the WebDriver process until the
action is complete (rather than spinning the WebContent process, which
we've seen result in deadlocks).
We currently spin the platform event loop while awaiting scripts to
complete. This causes WebContent to hang if another component is also
spinning the event loop. The particular example that instigated this
patch was the navigable's navigation loop (which spins until the fetch
process is complete), triggered by a form submission to an iframe.
So instead of spinning, we now return immediately from the script
executors, after setting up listeners for either the script's promise to
be resolved or for a timeout. The HTTP request to WebDriver must finish
synchronously though, so now the WebDriver process spins its event loop
until WebContent signals that the script completed. This should be ok -
the WebDriver process isn't expected to be doing anything else in the
meantime.
Also, as a consequence of these changes, we now actually handle time
outs. We were previously creating the timeout timer, but not starting
it.
First, this moves the WebDriver socket to the /tmp/websocket/ directory,
as WebDriver now creates multiple sockets per session. Those sockets are
now created with Core::LocalServer rather than manually setting up the
listening sockets (this was an existing FIXME which resolved some issues
I was hitting with creating a second listening socket).
WebDriver passes both socket paths to Browser via command line. Browser
continues to connect itself via one socket path, then forwards the other
socket path to the WebContent process created by the OOPWV. WebContent
then connects to WebDriver over this path.
WebContent will temporarily set the navigator.webdriver flag to true
after connecting to WebDriver. This will soon be moved to its own IPC to
be sent by WebDriver.
