Fix live preview reload for documentSaved events

[jasonsanjose]

Fix for #5185. Instead of relying on doc.url, simply use the Document.file.fullPath and let the server provide the expected URL.

[jasonsanjose]

Updated with fix for #5222. @gruehle ready for review.

[gruehle]

Naming nit: the term "instrumentationEnabled" doesn't really match the functionality. HTML documents are instrumented, but CSS documents aren't. How about using liveEditingEnabled instead? The function on CSSDocument/HTMLDocument would be called isLiveEditingEnabled().

[jasonsanjose]

fixed

[gruehle]

I'm seeing a failure in the Live Development unit tests: "should reapply in-memory css changes after saving changes in html document".

[gruehle]

Initial review complete.

[gruehle]

SpecRunnerUtils.getTempDirectory() is used several times in this file. This value should be in a variable.

[gruehle]

@jasonsanjose re-review complete. Still have one failing unit test.

[jasonsanjose]

@gruehle went a different route to fix the async bug in that test. Changed the tests to wait for the Inspector.Page loadEventFired event instead.

[jasonsanjose]

No need to restore file content now that we read the project from test/temp

[gruehle]

Everything is working well. It's too bad we need to wait 3 seconds for each of the tests that is expecting the page to not reload, but I can't think of an alternative.

Merging.